io_uring: remove init for unused list

poll*() doesn't use req->list, don't init it.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -4964,7 +4964,6 @@ static int io_poll_add(struct io_kiocb *req)
 	req->flags &= ~REQ_F_WORK_INITIALIZED;
 
 	INIT_HLIST_NODE(&req->hash_node);
-	INIT_LIST_HEAD(&req->list);
 	ipt.pt._qproc = io_poll_queue_proc;
 
 	mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,