documentation: Added new description for the PACKAGECONFIG_CONFARGS variable.

Fixes [YOCTO #10183]

Added a new variable entry for the PACKAGECONFIG_CONFARGS variable.

With the introduction of the new PACKAGECONFIG_CONFARGS variable,
many places in the mainstream YP documentation that referenced
how to pass configure arguments using EXTRA_OECONF needed to also
make mention of this new variable.  I added many cross-references
to the new variable.

(From yocto-docs rev: 00f02d45319bab90b72eab89fcb69cbe8bd05bb5)

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/dev-manual/dev-manual-common-tasks.xml

@@ -2297,6 +2297,8 @@
                         However, you might still want to make some adjustments.
                         For example, you can set
                         <ulink url='&YOCTO_DOCS_REF_URL;#var-EXTRA_OECONF'><filename>EXTRA_OECONF</filename></ulink>
+                        or
+                        <ulink url='&YOCTO_DOCS_REF_URL;#var-PACKAGECONFIG_CONFARGS'><filename>PACKAGECONFIG_CONFARGS</filename></ulink>
                         to pass any needed configure options that are specific
                         to the recipe.</para></listitem>
                     <listitem><para><emphasis>CMake:</emphasis>
@@ -3011,8 +3013,10 @@
                     You do not need to add a <filename>do_compile</filename> step since by default BitBake
                     starts the <filename>make</filename> command to compile the application.
                     If you need additional <filename>make</filename> options, you should store them in the
-                    <filename><ulink url='&YOCTO_DOCS_REF_URL;#var-EXTRA_OEMAKE'>EXTRA_OEMAKE</ulink></filename>
-                    variable.
+                    <ulink url='&YOCTO_DOCS_REF_URL;#var-EXTRA_OEMAKE'><filename>EXTRA_OEMAKE</filename></ulink>
+                    or
+                    <ulink url='&YOCTO_DOCS_REF_URL;#var-PACKAGECONFIG_CONFARGS'><filename>PACKAGECONFIG_CONFARGS</filename></ulink>
+                    variables.
                     BitBake passes these options into the GNU <filename>make</filename> invocation.
                     Note that a <filename>do_install</filename> task is still required.
                     Otherwise, BitBake runs an empty <filename>do_install</filename> task by default.