ref-manual: Added new variable entry for BULIDDIR.

Ross Burton suggested this might be good to have so I added
it.  The changes include the entry itself and a link to it
from the beginning of the "Classes" chapter where it is
talked about.

Reported-by: Ross Burton <ross.burton@intel.com>
(From yocto-docs rev: 5b0263fa5e01706ccb815db51b8f1b7f86275721)

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

1 files changed, 2 insertions, 1 deletions

diff --git a/documentation/ref-manual/ref-classes.xml b/documentation/ref-manual/ref-classes.xml
index 9cc7ad134a..529f89c3d8 100644
--- a/documentation/ref-manual/ref-classes.xml
+++ b/documentation/ref-manual/ref-classes.xml
@@ -15,7 +15,8 @@
     in a <filename>classes/</filename> directory beneath the
     <filename>meta*/</filename> directory found in the
     <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>.
-    Class files can also be pointed to by <filename>BUILDDIR</filename>
+    Class files can also be pointed to by
+    <link linkend='var-BUILDDIR'><filename>BUILDDIR</filename></link>
     (e.g. <filename>build/</filename>)in the same way as
     <filename>.conf</filename> files in the <filename>conf</filename> directory.
     Class files are searched for in <link linkend='var-BBPATH'><filename>BBPATH</filename></link>