Drop duplicate CONFIG_SYS_NO_FLASH from mx6_common

It's defind earlier in the file

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
diff --git a/include/configs/mx6_common.h b/include/configs/mx6_common.h
index 50370e1..b37477a 100644
--- a/include/configs/mx6_common.h
+++ b/include/configs/mx6_common.h
@@ -87,7 +87,6 @@
 #define CONFIG_CMD_FAT
 
 /* Miscellaneous configurable options */
-#define CONFIG_SYS_NO_FLASH
 #undef CONFIG_CMD_IMLS
 #define CONFIG_SYS_LONGHELP
 #define CONFIG_SYS_HUSH_PARSER