nvme: simplify nvme_req_qid()

Use the request's '->mq_hctx->queue_num' directly to simplify the
nvme_req_qid() function.
Signed-off-by: NBaolin Wang <baolin.wang@linux.alibaba.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

drivers/nvme/host/nvme.h

@@ -178,7 +178,8 @@ static inline u16 nvme_req_qid(struct request *req)
 {
 	if (!req->q->queuedata)
 		return 0;
-	return blk_mq_unique_tag_to_hwq(blk_mq_unique_tag(req)) + 1;
+
+	return req->mq_hctx->queue_num + 1;
 }
 
 /* The below value is the specific amount of delay needed before checking