82xx, mgcoge: fix environment sector size

Size of one environment sector is 0x20000.

Signed-off-by: Heiko Schocher <hs@denx.de>

include/configs/mgcoge.h

@@ -145,7 +145,7 @@
 #define CONFIG_ENV_IS_IN_FLASH
 
 #ifdef CONFIG_ENV_IS_IN_FLASH
-#define CONFIG_ENV_SECT_SIZE	0x4000
+#define CONFIG_ENV_SECT_SIZE	0x20000
 #define CONFIG_ENV_ADDR		(CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
 #define CONFIG_ENV_OFFSET	CONFIG_SYS_MONITOR_LEN