powerpc/mpc85xx:Update MONITOR_LEN for 768KB u-boot size

U-boot binary size has been increased from 512KB to 768KB.

So update CONFIG_SYS_MONITOR_LEN to reflect the same.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/include/configs/P2041RDB.h b/include/configs/P2041RDB.h
index f024c29..54e6493 100644
--- a/include/configs/P2041RDB.h
+++ b/include/configs/P2041RDB.h
@@ -315,7 +315,7 @@
 					GENERATED_GBL_DATA_SIZE)
 #define CONFIG_SYS_INIT_SP_OFFSET	CONFIG_SYS_GBL_DATA_OFFSET
 
-#define CONFIG_SYS_MONITOR_LEN		(512 * 1024)
+#define CONFIG_SYS_MONITOR_LEN		(768 * 1024)
 #define CONFIG_SYS_MALLOC_LEN		(1024 * 1024)
 
 /* Serial Port - controlled on board with jumper J8