ARM: da850-evm: Enable SPI Flash and NAND Flash when booting NOR

Historically there have been various boot options, SPI flash,
NAND or NOR. The NOR flash is mutually exclusive with MMC, but
it isn't mutually exclusive with NAND or SPI Flash, so this patch
enables both NAND flash and SPI Flash when booting from NOR.

Signed-off-by: Adam Ford <aford173@gmail.com>