manuals: improve references to classes

- Simplify references to class sections, by replacing references such as
  :ref:`image.bbclass <ref-classes-image>`
  by
  :ref:`ref-classes-image`

  That's equivalent, because the class sections always called <class>.bbclass

- Adding references to class sections, by replacing strings such as
  ``image.bbclass``
  by
  :ref:`ref-classes-image`

- Simplifying a few class section links

(From yocto-docs rev: 29d66aaa898390c19f121baf0f4fdcc178e4cd80)

Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/release-process.rst

@@ -117,17 +117,17 @@ consists of the following pieces:
 -  ``bitbake-selftest``: A standalone command that runs unit tests on
    key pieces of BitBake and its fetchers.
 
--  :ref:`sanity.bbclass <ref-classes-sanity>`: This automatically
+-  :ref:`ref-classes-sanity`: This automatically
    included class checks the build environment for missing tools (e.g.
    ``gcc``) or common misconfigurations such as
    :term:`MACHINE` set incorrectly.
 
--  :ref:`insane.bbclass <ref-classes-insane>`: This class checks the
+-  :ref:`ref-classes-insane`: This class checks the
    generated output from builds for sanity. For example, if building for
    an ARM target, did the build produce ARM binaries. If, for example,
    the build produced PPC binaries then there is a problem.
 
--  :ref:`testimage.bbclass <ref-classes-testimage*>`: This class
+-  :ref:`ref-classes-testimage*`: This class
    performs runtime testing of images after they are built. The tests
    are usually used with :doc:`QEMU </dev-manual/qemu>`
    to boot the images and check the combined runtime result boot

documentation/ref-manual/structure.rst

@@ -667,16 +667,17 @@ Yocto Project. Metadata has several important subdivisions:
 
 This directory contains the ``*.bbclass`` files. Class files are used to
 abstract common code so it can be reused by multiple packages. Every
-package inherits the ``base.bbclass`` file. Examples of other important
-classes are ``autotools.bbclass``, which in theory allows any
+package inherits the :ref:`ref-classes-base` file. Examples of other important
+classes are :ref:`ref-classes-autotools`, which in theory allows any
 Autotool-enabled package to work with the Yocto Project with minimal
-effort. Another example is ``kernel.bbclass`` that contains common code
+effort. Another example is :ref:`ref-classes-kernel` that contains common code
 and functions for working with the Linux kernel. Functions like image
 generation or packaging also have their specific class files such as
-``image.bbclass``, ``rootfs_*.bbclass`` and ``package*.bbclass``.
+:ref:`ref-classes-image`, :ref:`ref-classes-rootfs*` and
+:ref:`package*.bbclass <ref-classes-package>`.
 
 For reference information on classes, see the
-":ref:`ref-manual/classes:Classes`" chapter.
+":doc:`/ref-manual/classes`" chapter.
 
 .. _structure-meta-conf:
 

documentation/ref-manual/variables.rst

@@ -971,7 +971,7 @@ system and gives an overview of their function and contents.
       When inheriting the :ref:`buildhistory <ref-classes-buildhistory>`
       class, this variable specifies the directory in which build history
       information is kept. For more information on how the variable works,
-      see the ``buildhistory.bbclass`` file.
+      see the :ref:`ref-classes-buildhistory` class.
 
       By default, the :ref:`buildhistory <ref-classes-buildhistory>` class sets the directory as follows::
 
@@ -2162,8 +2162,7 @@ system and gives an overview of their function and contents.
       :term:`S` variable, which is what the OpenEmbedded build
       system uses to locate unpacked recipe source code.
 
-      For more information on ``externalsrc.bbclass``, see the
-      ":ref:`ref-classes-externalsrc`" section. You
+      See the ":ref:`ref-classes-externalsrc`" section for details. You
       can also find information on how to use this variable in the
       ":ref:`dev-manual/common-tasks:building software from an external source`"
       section in the Yocto Project Development Tasks Manual.
@@ -2176,8 +2175,7 @@ system and gives an overview of their function and contents.
       which is what the OpenEmbedded build system uses to locate the Build
       Directory.
 
-      For more information on ``externalsrc.bbclass``, see the
-      ":ref:`ref-classes-externalsrc`" section. You
+      See the ":ref:`ref-classes-externalsrc`" section for details. You
       can also find information on how to use this variable in the
       ":ref:`dev-manual/common-tasks:building software from an external source`"
       section in the Yocto Project Development Tasks Manual.
@@ -2501,7 +2499,7 @@ system and gives an overview of their function and contents.
       :term:`SRC_URI` statements.
 
       The default value for the :term:`FILESPATH` variable is defined in the
-      ``base.bbclass`` class found in ``meta/classes`` in the
+      :ref:`ref-classes-base` class found in ``meta/classes`` in the
       :term:`Source Directory`::
 
          FILESPATH = "${@base_set_filespath(["${FILE_DIRNAME}/${BP}", \
@@ -3085,7 +3083,7 @@ system and gives an overview of their function and contents.
       :term:`IMAGE_INSTALL` variable with care to avoid ordering issues.
 
       Image recipes set :term:`IMAGE_INSTALL` to specify the packages to
-      install into an image through ``image.bbclass``. Additionally,
+      install into an image through :ref:`ref-classes-image`. Additionally,
       there are "helper" classes such as the
       :ref:`core-image <ref-classes-core-image>` class which can
       take lists used with :term:`IMAGE_FEATURES` and turn them into
@@ -3118,7 +3116,7 @@ system and gives an overview of their function and contents.
             BitBake operator within the ``/conf/local.conf`` file or from
             within an image recipe is not recommended. Use of this operator
             in these ways can cause ordering issues. Since
-            ``core-image.bbclass`` sets :term:`IMAGE_INSTALL` to a default
+            :ref:`ref-classes-core-image` sets :term:`IMAGE_INSTALL` to a default
             value using the
             :ref:`?= <bitbake:bitbake-user-manual/bitbake-user-manual-metadata:setting a default value (?=)>`
             operator, using a ``+=`` operation against :term:`IMAGE_INSTALL`
@@ -3708,7 +3706,7 @@ system and gives an overview of their function and contents.
       The filename of the initialization script as installed to
       ``${sysconfdir}/init.d``.
 
-      This variable is used in recipes when using ``update-rc.d.bbclass``.
+      This variable is used in recipes when using :ref:`ref-classes-update-rc.d`.
       The variable is mandatory.
 
    :term:`INITSCRIPT_PACKAGES`
@@ -3716,7 +3714,7 @@ system and gives an overview of their function and contents.
       are specified, you need to append the package name to the other
       ``INITSCRIPT_*`` as an override.
 
-      This variable is used in recipes when using ``update-rc.d.bbclass``.
+      This variable is used in recipes when using :ref:`ref-classes-update-rc.d`.
       The variable is optional and defaults to the :term:`PN`
       variable.
 
@@ -6346,7 +6344,7 @@ system and gives an overview of their function and contents.
       In the
       example, the package name (``${PN}-dev``) must appear as it would in
       the :term:`PACKAGES` namespace before any renaming of the output package
-      by classes such as ``debian.bbclass``.
+      by classes such as :ref:`ref-classes-debian`.
 
       BitBake, which the OpenEmbedded build system uses, supports
       specifying versioned recommends. Although the syntax varies depending