ref-manual: Added BUILDHISTORY_DIR_PACKAGE to the glossary.

(From yocto-docs rev: 0e70c4cd0a7c238aefa2a9ec37e89163d541d4a7)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/ref-variables.xml

@@ -941,6 +941,30 @@
             </glossdef>
         </glossentry>
 
+        <glossentry id='var-BUILDHISTORY_DIR_PACKAGE'><glossterm>BUILDHISTORY_DIR_PACKAGE</glossterm>
+            <glossdef>
+                <para>
+                    When inheriting the
+                    <link linkend='ref-classes-buildhistory'><filename>buildhistory</filename></link>
+                    class, specifies the name of the package analyzed using
+                    the build history feature.
+                    For more information on how the variable works, see the
+                    <filename>buildhistory.class</filename>.
+                    For more information on how build history works, see the
+                    "<link linkend='maintaining-build-output-quality'>Maintaining Build Output Quality</link>"
+                    section.
+                </para>
+
+                <para>
+                    By default, the <filename>buildhistory</filename> class
+                    sets the package name as follows:
+                    <literallayout class='monospaced'>
+     BUILDHISTORY_DIR_PACKAGE = "${BUILDHISTORY_DIR}/packages/${MULTIMACH_TARGET_SYS}/${PN}"
+                    </literallayout>
+                </para>
+            </glossdef>
+        </glossentry>
+
         <glossentry id='var-BUILDHISTORY_FEATURES'><glossterm>BUILDHISTORY_FEATURES</glossterm>
             <glossdef>
                 <para>