io_uring: fix __io_uring_files_cancel() with TASK_UNINTERRUPTIBLE

io_uring: fix __io_uring_files_cancel() with TASK_UNINTERRUPTIBLE

[ Upstream commit a1bb3cd58913338e1b627ea6b8c03c2ae82d293f ]

If the tctx inflight number haven't changed because of cancellation,
__io_uring_task_cancel() will continue leaving the task in
TASK_UNINTERRUPTIBLE state, that's not expected by
__io_uring_files_cancel(). Ensure we always call finish_wait() before
retrying.

Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>