io_uring: remove iopoll_queue from struct io_issue_def

io_uring: remove iopoll_queue from struct io_issue_def

The opcode iopoll_queue flag is now redundant with REQ_F_IOPOLL. Only
io_{read,write}{,_fixed}() and io_uring_cmd() set the REQ_F_IOPOLL flag,
and the opcodes with these ->issue() implementations are precisely the
ones that set iopoll_queue. So don't bother checking the iopoll_queue
flag in io_issue_sqe(). Remove the unused flag from struct io_issue_def.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://patch.msgid.link/20260302172914.2488599-3-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>