mtd: spi-nor: fix nor->addr_width when its value configured from SFDP does not match...

mtd: spi-nor: fix nor->addr_width when its value configured from SFDP does not match the actual width

IS25LP256 gets BFPT_DWORD1_ADDRESS_BYTES_3_ONLY from BFPT table for
address width. But in actual fact the flash can support 4-byte address.
Use a post bfpt fixup hook to overwrite the address width advertised by
the BFPT.

Signed-off-by: Liu Xiang <liu.xiang6@zte.com.cn>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>