io_uring/rsrc: remove redundant __set_current_state() post schedule()

We're guaranteed to be in a TASK_RUNNING state post schedule, so we
never need to set the state after that. While in there, remove the
other __set_current_state() as well, and just call finish_wait()
when we now we're going to break anyway. This is easier to grok than
manual __set_current_state() calls.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>