block: don't use bio_has_data() in the completion path

We should just check for rq->bio, as that is really the information
we are looking for. Even if the bio attached doesn't carry data,
we still need to do IO post processing on it.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

block/blk-core.c

@@ -1817,7 +1817,7 @@ static int blk_end_io(struct request *rq, int error, unsigned int nr_bytes,
 	struct request_queue *q = rq->q;
 	unsigned long flags = 0UL;
 
-	if (bio_has_data(rq->bio) || blk_discard_rq(rq)) {
+	if (rq->bio) {
 		if (__end_that_request_first(rq, error, nr_bytes))
 			return 1;
 
@@ -1875,8 +1875,7 @@ EXPORT_SYMBOL_GPL(blk_end_request);
  **/
 int __blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
 {
-	if ((bio_has_data(rq->bio) || blk_discard_rq(rq)) &&
-	    __end_that_request_first(rq, error, nr_bytes))
+	if (rq->bio && __end_that_request_first(rq, error, nr_bytes))
 		return 1;
 
 	add_disk_randomness(rq->rq_disk);