mpc8xx: remove rbc823 board support

This board is old enough and has no maintainer.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/include/commproc.h b/include/commproc.h
index ef59df9..d53cbdd 100644
--- a/include/commproc.h
+++ b/include/commproc.h
@@ -968,7 +968,7 @@
 /***  MVS1, TQM823L/M, TQM850L/M, TQM885D, R360MPI  **********/
 
 #if (defined(CONFIG_MVS) && CONFIG_MVS < 2) || \
-    defined(CONFIG_R360MPI) || defined(CONFIG_RBC823)  || \
+    defined(CONFIG_R360MPI) || \
     defined(CONFIG_RRVISION)|| defined(CONFIG_TQM823L) || \
     defined(CONFIG_TQM823M) || defined(CONFIG_TQM850L) || \
     defined(CONFIG_TQM850M) || defined(CONFIG_TQM885D) || \