blk-mq: switch ->queue_rq return value to blk_status_t

Use the same values for use for request completion errors as the return
value from ->queue_rq.  BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 3e8b43d..74a6791 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -4154,14 +4154,14 @@
 	blk_mq_end_request(rq, errno_to_blk_status(result));
 }
 
-static int rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
+static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
 		const struct blk_mq_queue_data *bd)
 {
 	struct request *rq = bd->rq;
 	struct work_struct *work = blk_mq_rq_to_pdu(rq);
 
 	queue_work(rbd_wq, work);
-	return BLK_MQ_RQ_QUEUE_OK;
+	return BLK_STS_OK;
 }
 
 static void rbd_free_disk(struct rbd_device *rbd_dev)