Use the same logic to prepare RD/WRPROTECT and the protection
operation. Fixes a corner case where we could issue an unprotected
CDB and yet tell the HBA to do DIF to the drive.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>