uboot-imx

Remove unused symbol CONGIG_CMD_STORAGE from board configs

Albeit it's a typo, neither CONGIG_CMD_STORAGE nor CONFIG_CMD_STORAGE
are used anywhere, so remove the define from the board configs.

Signed-off-by: Lars Poeschel <poeschel@lemonage.de>
Reviewed-by: Tom Rini <trini@konsulko.com>