io_uring: get rid of __io_fill_cqe{32}_req()

There are too many cqe filling helpers, kill __io_fill_cqe{32}_req(),
use __io_fill_cqe{32}_req_filled() instead, and then rename it. It'll
simplify fixing in following patches.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c18e0d191014fb574f24721245e4e3fddd0b6917.1655287457.git.asml.silence@gmail.com


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