docs: fix new override syntax migration

Fix bits missed by the migration script.

(From yocto-docs rev: 452e0c5067476fd2ce81f09e6c73da84ced4bbd0)

Signed-off-by: Quentin Schulz <foss@0leil.net>
Reviewed-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/overview-manual/concepts.rst

@@ -1768,7 +1768,7 @@ It is also worth noting that the end result of these signature
 generators is to make some dependency and hash information available to
 the build. This information includes:
 
--  ``BB_BASEHASH_task-``\ taskname: The base hashes for each task in the
+-  ``BB_BASEHASH:task-``\ taskname: The base hashes for each task in the
    recipe.
 
 -  ``BB_BASEHASH_``\ filename\ ``:``\ taskname: The base hashes for each
@@ -2027,7 +2027,7 @@ dependencies, you must manually declare the dependencies.
    .. note::
 
       By default, ``foo-dev`` also has an :term:`RDEPENDS`-style dependency on
-      ``foo``, because the default value of ``RDEPENDS_${PN}-dev`` (set in
+      ``foo``, because the default value of ``RDEPENDS:${PN}-dev`` (set in
       bitbake.conf) includes "${PN}".
 
    To ensure that the dependency chain is never broken, ``-dev`` and

documentation/overview-manual/yp-intro.rst

@@ -738,7 +738,7 @@ other build process, in which case the basic functionality can be
 defined by the classes it inherits from the OE-Core layer's class
 definitions in ``./meta/classes``. Within a recipe you can also define
 additional tasks as well as task prerequisites. Recipe syntax through
-BitBake also supports both ``_prepend`` and ``_append`` operators as a
+BitBake also supports both ``:prepend`` and ``:append`` operators as a
 method of extending task functionality. These operators inject code into
 the beginning or end of a task. For information on these BitBake
 operators, see the