blk-mq: move blk_mq_flush_plug_list to block/blk-mq.h

This helper is internal to the block layer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211020144119.142582-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-mq.h

@@ -122,6 +122,7 @@ extern int blk_mq_sysfs_register(struct request_queue *q);
 extern void blk_mq_sysfs_unregister(struct request_queue *q);
 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
 void blk_mq_free_plug_rqs(struct blk_plug *plug);
+void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
 
 void blk_mq_release(struct request_queue *q);
 

include/linux/blk-mq.h

@@ -656,8 +656,6 @@ int blk_mq_alloc_sq_tag_set(struct blk_mq_tag_set *set,
 		unsigned int set_flags);
 void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
 
-void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
-
 void blk_mq_free_request(struct request *rq);
 
 bool blk_mq_queue_inflight(struct request_queue *q);