[SCSI] scsi_lib: use blk_rq_tagged in scsi_request_fn

I goofed and did not see the macro for checking if a request is tagged.
This patch has us use blk_rq_tagged instead of digging into the req->tag.

Patch was made over scsi-misc.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/scsi_lib.c

@@ -1533,7 +1533,7 @@ static void scsi_request_fn(struct request_queue *q)
 		 * we add the dev to the starved list so it eventually gets
 		 * a run when a tag is freed.
 		 */
-		if (blk_queue_tagged(q) && (req->tag == -1)) {
+		if (blk_queue_tagged(q) && !blk_rq_tagged(req)) {
 			if (list_empty(&sdev->starved_entry))
 				list_add_tail(&sdev->starved_entry,
 					      &shost->starved_list);