[SCSI] qla2xxx: Mask out 'reserved' bits while processing FLT regions.

Bits 31-8 are marked as reserved and should be ignored while
interpreting a region's code.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>