powerpc: mpc5xxx: remove redundant CONFIG_MPC5xxx definition

We do not have to define CONFIG_MPC5xxx in board config headers
(and start.S) because it is defined in arch/powerpc/cpu/mpc5xxx/config.mk.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/include/configs/aev.h b/include/configs/aev.h
index 0eafb3c..2dffcfb 100644
--- a/include/configs/aev.h
+++ b/include/configs/aev.h
@@ -16,8 +16,7 @@
  * (easy to change)
  */
 
-#define CONFIG_MPC5xxx		1	/* This is an MPC5xxx CPU */
-#define CONFIG_MPC5200		1	/* (more precisely an MPC5200 CPU) */
+#define CONFIG_MPC5200		1	/* This is an MPC5200 CPU */
 #define CONFIG_TQM5200		1	/* ... on TQM5200 module */
 #undef CONFIG_TQM5200_REV100		/*  define for revision 100 modules */
 #define CONFIG_STK52XX		1	/* ... on a STK52XX base board */