io_uring: simplify io_req_link_next()

"if (nxt)" is always true, as it was checked in the while's condition.
io_wq_current_is_worker() is unnecessary, as non-async callers don't
pass nxt, so io_queue_async_work() will be called for them anyway.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -903,16 +903,7 @@ static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr)
 			nxt->flags |= REQ_F_LINK;
 		}
 
-		/*
-		 * If we're in async work, we can continue processing the chain
-		 * in this context instead of having to queue up new async work.
-		 */
-		if (nxt) {
-			if (io_wq_current_is_worker())
-				*nxtptr = nxt;
-			else
-				io_queue_async_work(nxt);
-		}
+		*nxtptr = nxt;
 		break;
 	}