io_uring: unify calling convention for async prep handling

Make them consistent in preparation for defining a req async prep
handler. The readv/writev requests share a prep handler, move it one
level down so the initial one is consistent with the others.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2022-05-23 17:16:21 -06:00
commit 157dc813b4