io_uring: remove io_prep_next_work()

io-wq cares about IO_WQ_WORK_UNBOUND flag only while enqueueing, so
it's useless setting it for a next req of a link. Thus, removed it
from io_prep_linked_timeout(), and inline the function.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -999,17 +999,6 @@ static inline void io_req_work_drop_env(struct io_kiocb *req)
 	}
 }
 
-static inline void io_prep_next_work(struct io_kiocb *req,
-				     struct io_kiocb **link)
-{
-	const struct io_op_def *def = &io_op_defs[req->opcode];
-
-	if (!(req->flags & REQ_F_ISREG) && def->unbound_nonreg_file)
-		req->work.flags |= IO_WQ_WORK_UNBOUND;
-
-	*link = io_prep_linked_timeout(req);
-}
-
 static inline bool io_prep_async_work(struct io_kiocb *req,
 				      struct io_kiocb **link)
 {
@@ -2581,8 +2570,8 @@ static void io_wq_assign_next(struct io_wq_work **workptr, struct io_kiocb *nxt)
 {
 	struct io_kiocb *link;
 
-	io_prep_next_work(nxt, &link);
 	*workptr = &nxt->work;
+	link = io_prep_linked_timeout(nxt);
 	if (link) {
 		nxt->work.func = io_link_work_cb;
 		nxt->work.data = link;