mkconfig: Create board directory (CONFIG_BOARDDIR) in include/config.h

This patch extends the mkconfig script to automatically create a define
for the board directory in include/config.h:

#define CONFIG_BOARDDIR board/amcc/canyonlands

This is needed for the upcoming PPC4xx linker script consolidation,
where the PPC440 platforms need to include a board specific file in
the common linker script.
Signed-off-by: NStefan Roese <sr@denx.de>

mkconfig

@@ -74,6 +74,13 @@ echo "BOARD  = $4" >> config.mk
 
 [ "$6" ] && [ "$6" != "NULL" ] && echo "SOC    = $6" >> config.mk
 
+# Assign board directory to BOARDIR variable
+if [ -z "$5" -o "$5" = "NULL" ] ; then
+    BOARDDIR=$4
+else
+    BOARDDIR=$5/$4
+fi
+
 #
 # Create board specific header file
 #
@@ -89,6 +96,8 @@ for i in ${TARGETS} ; do
 	echo "#define CONFIG_MK_${i} 1" >>config.h ;
 done
 
+echo "#define CONFIG_BOARDDIR board/$BOARDDIR" >>config.h
+
 echo "#include <configs/$1.h>" >>config.h
 echo "#include <asm/config.h>" >>config.h