blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request

Instead of having two almost identical copies of the same code just let
the callers pass in the reserved flag directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 29d5fba..d87be5b 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1173,7 +1173,7 @@
 struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask)
 {
 	if (q->mq_ops)
-		return blk_mq_alloc_request(q, rw, gfp_mask);
+		return blk_mq_alloc_request(q, rw, gfp_mask, false);
 	else
 		return blk_old_get_request(q, rw, gfp_mask);
 }