[SCSI] Fix range check in scsi_host_dif_capable()

The range checking from fe542396 was bad. We would still end up walking
beyond the array as Type 3 is defined to be 4 in the protection
bitmask. Instead use ARRAY_SIZE() for the range check.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

include/scsi/scsi_host.h

@@ -873,7 +873,7 @@ static inline unsigned int scsi_host_dif_capable(struct Scsi_Host *shost, unsign
 				       SHOST_DIF_TYPE2_PROTECTION,
 				       SHOST_DIF_TYPE3_PROTECTION };
 
-	if (target_type > SHOST_DIF_TYPE3_PROTECTION)
+	if (target_type >= ARRAY_SIZE(cap))
 		return 0;
 
 	return shost->prot_capabilities & cap[target_type] ? target_type : 0;
@@ -887,7 +887,7 @@ static inline unsigned int scsi_host_dix_capable(struct Scsi_Host *shost, unsign
 				       SHOST_DIX_TYPE2_PROTECTION,
 				       SHOST_DIX_TYPE3_PROTECTION };
 
-	if (target_type > SHOST_DIX_TYPE3_PROTECTION)
+	if (target_type >= ARRAY_SIZE(cap))
 		return 0;
 
 	return shost->prot_capabilities & cap[target_type];