[DRIVERS] Correcting the M25P80 flash block device driver.

The flash information structure required is in the request queue private field,
not in the request one.

Signed-off-by: Jimmy Durand Wesolowski <jimmy.durand-wesolowski@openwide.fr>
[DRIVERS] Using the block device NOP strategy on the M25P80 flash driver.

Signed-off-by: Jimmy Durand Wesolowski <jimmy.durand-wesolowski@openwide.fr>
Signed-off-by: Anup Patel <anup@brainfault.org>