ref-manual: Updated PACKAGES_FEED_ARCHS variable

Added the fact that this variable is really optional.  If  you
don't use it then you are setting up a package feed URI that
will include all supported arcchitectures for the package.
Using it means you are setting up specific URIs for specific
architectures.

Added a "Tip" note box to show how you can use the variable
to whitelist architectures.

(From yocto-docs rev: 009f3551aa61aaf6459fd24105a2e06511b59da3)

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

1 files changed, 15 insertions, 6 deletions

diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 705b1977d8..7ba1c576f6 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -9594,20 +9594,29 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
 
         <glossentry id='var-PACKAGE_FEED_ARCHS'><glossterm>PACKAGE_FEED_ARCHS</glossterm>
             <info>
-                PACKAGE_FEED_ARCHS[doc] = "Specifies user-defined package architectures when constructing package feed URIs."
+                PACKAGE_FEED_ARCHS[doc] = "Optionally specifies user-defined package architectures when constructing package feed URIs."
             </info>
             <glossdef>
                 <para role="glossdeffirst">
 <!--                <para role="glossdeffirst"><imagedata fileref="figures/define-generic.png" /> -->
-                    Specifies the package architectures used as part of the
-                    package feed URIs during the build.
-                    The <filename>PACKAGE_FEED_ARCHS</filename> variable is
-                    appended to the final package feed URI, which is constructed
-                    using the
+                    Optionally specifies the package architectures used as
+                    part of the package feed URIs during the build.
+                    When used, the <filename>PACKAGE_FEED_ARCHS</filename>
+                    variable is appended to the final package feed URI, which
+                    is constructed using the
                     <link linkend='var-PACKAGE_FEED_URIS'><filename>PACKAGE_FEED_URIS</filename></link>
                     and
                     <link linkend='var-PACKAGE_FEED_BASE_PATHS'><filename>PACKAGE_FEED_BASE_PATHS</filename></link>
                     variables.
+                    <note><title>Tip</title>
+                        You can use the <filename>PACKAGE_FEEDS_ARCHS</filename>
+                        variable to whitelist specific package architectures.
+                        If you do not need to whitelist specific architectures,
+                        which is a common case, you can omit this variable.
+                        Omitting the variable results in all available
+                        architectures for the current machine being included
+                        into remote package feeds.
+                    </note>
                 </para>
 
                 <para>