io_uring: inline __tctx_task_work()

Inline __tctx_task_work() into tctx_task_work() in preparation for
further optimisations.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f9c05c4bc9763af7bd8e25ebc3c5f7b6f69148f8.1623949695.git.asml.silence@gmail.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>