[SCSI] qla2xxx: Fix flash write failure on ISP82xx.

Driver was not unprotecting correctly, use correct bits
to unprotect the flash on ISP 82xx.

Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>