powerpc/p2041rdb: add env in NAND support

Add env in NAND support when boot from NAND.
Signed-off-by: NShaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>

include/configs/P2041RDB.h

@@ -96,6 +96,11 @@
 	#define CONFIG_SYS_MMC_ENV_DEV          0
 	#define CONFIG_ENV_SIZE			0x2000
 	#define CONFIG_ENV_OFFSET		(512 * 1097)
+#elif defined(CONFIG_NAND)
+#define CONFIG_SYS_EXTRA_ENV_RELOC
+#define CONFIG_ENV_IS_IN_NAND
+#define CONFIG_ENV_SIZE			CONFIG_SYS_NAND_BLOCK_SIZE
+#define CONFIG_ENV_OFFSET		(5 * CONFIG_SYS_NAND_BLOCK_SIZE)
 #else
 	#define CONFIG_ENV_IS_IN_FLASH
 	#define CONFIG_ENV_ADDR		(CONFIG_SYS_MONITOR_BASE \