spi: Add Winbond w25q256fw flash memory

commit 657834aad5cfd00ea95eb15a1feb7c7c17737573 from
git@git.assembla.com:cavium/WindRiver.linux.git

Add w25q256fw JEDEC ID.

Signed-off-by: Witold Sadowski <wsadowski@marvell.com>
Change-Id: Idfd55cfff131af13593c03b197ba29afbc6b489c
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/69947
Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Chandrakala Chavva <cchavva@marvell.com>
[RQ: Apply patch to drivers/mtd/spi-nor/winbond.c]
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>