mtd: spi-nor: enable stateless 4b op codes for mx25u25635f

All required stateless 4-byte op codes are supported by this flash
chip. The stateless 4-byte support can't be autodetected due to a
missing 4-byte Address Instruction Table in SFDP.

Fixes hangs on reboot for SoCs expecting the flash chip in 3byte mode.

Signed-off-by: Mathias Kresin <dev@kresin.me>
Acked-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>