hpsa: correct decode sense data

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kevin Barnett <kevin.barnett@pmcs.com>
Reviewed-by: Scott Teel <scott.teel@pmcs.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Don Brace <don.brace@pmcs.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

drivers/scsi/hpsa.c

@@ -325,7 +325,7 @@ static int check_for_unit_attention(struct ctlr_info *h,
 
 	decode_sense_data(c->err_info->SenseInfo, sense_len,
 				&sense_key, &asc, &ascq);
-	if (sense_key != UNIT_ATTENTION || asc == -1)
+	if (sense_key != UNIT_ATTENTION || asc == 0xff)
 		return 0;
 
 	switch (asc) {