io_uring/notif: refactor io_tx_ubuf_complete()

Flip the dec_and_test "if", that makes the function extension easier in
the future.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/43939e2b04dff03bff5d7227c98afedf951227b3.1713185320.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

io_uring/notif.c

@@ -37,10 +37,11 @@ static void io_tx_ubuf_callback(struct sk_buff *skb, struct ubuf_info *uarg,
 			WRITE_ONCE(nd->zc_copied, true);
 	}
 
-	if (refcount_dec_and_test(&uarg->refcnt)) {
-		notif->io_task_work.func = io_notif_tw_complete;
-		__io_req_task_work_add(notif, IOU_F_TWQ_LAZY_WAKE);
-	}
+	if (!refcount_dec_and_test(&uarg->refcnt))
+		return;
+
+	notif->io_task_work.func = io_notif_tw_complete;
+	__io_req_task_work_add(notif, IOU_F_TWQ_LAZY_WAKE);
 }
 
 struct io_kiocb *io_alloc_notif(struct io_ring_ctx *ctx)