ppc: cleanup compiler errors/warnings

Current u-boot top of tree builds with warnings/errors for
the following boards:

ads5121 cpci5200 mecp5200 v38b IAD210 MBX MBX860T NX823
RPXClassic debris PN62

following patch solves this.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/configs/MBX860T.h b/include/configs/MBX860T.h
index 0c28710..afe2383 100644
--- a/include/configs/MBX860T.h
+++ b/include/configs/MBX860T.h
@@ -381,6 +381,7 @@
 */
 #define NR_8259_INTS	0
 
+#define CONFIG_CMD_NET
 /*
  * MPC8xx CPM Options
  */