ppc4xx: Fix default environment for AMCC boards

Commit 0ad7f0950a [ppc4xx: cleanup
default environment for AMCC boards] broke the default env for
many PPC4xx boards. The '\0' character got removed at the end
of some environment commands like "update". This patch adds the
missing '\0' characters again.

Signed-off-by: Stefan Roese <sr@denx.de>

include/configs/amcc-common.h

@@ -271,13 +271,13 @@
 	"load=tftp 200000 ${u-boot}\0"					\
 	"update=protect off " xstr(CONFIG_SYS_MONITOR_BASE) " FFFFFFFF;"	\
 		"era " xstr(CONFIG_SYS_MONITOR_BASE) " FFFFFFFF;"		\
-		"cp.b ${fileaddr} " xstr(CONFIG_SYS_MONITOR_BASE) " ${filesize}" \
+		"cp.b ${fileaddr} " xstr(CONFIG_SYS_MONITOR_BASE) " ${filesize}\0" \
 	"upd=run load update\0"						\
 
 #define CONFIG_AMCC_DEF_ENV_NAND_UPD					\
 	"u-boot-nand=" xstr(CONFIG_HOSTNAME) "/u-boot-nand.bin\0"	\
 	"nload=tftp 200000 ${u-boot-nand}\0"				\
-	"nupdate=nand erase 0 100000;nand write 200000 0 100000"	\
+	"nupdate=nand erase 0 100000;nand write 200000 0 100000\0"	\
 	"nupd=run nload nupdate\0"
 
 #endif /* __AMCC_COMMON_H */