io_uring: end waiting before task cancel attempts

Get rid of TASK_UNINTERRUPTIBLE and waiting with finish_wait before
going for next iteration in __io_uring_task_cancel(), because
__io_uring_files_cancel() doesn't expect that sheduling is disallowed.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -8989,9 +8989,9 @@ void __io_uring_task_cancel(void)
 		if (inflight != tctx_inflight(tctx))
 			continue;
 		schedule();
+		finish_wait(&tctx->wait, &wait);
 	} while (1);
 
-	finish_wait(&tctx->wait, &wait);
 	atomic_dec(&tctx->in_idle);
 }