io_uring/io-wq: inherit cpuset of cgroup in io worker

io_uring/io-wq: inherit cpuset of cgroup in io worker

The io worker threads are userland threads that just never exit to the
userland. By that, they are also assigned to a cgroup (the group of the
creating task).

When creating a new io worker, this worker should inherit the cpuset
of the cgroup.

Fixes: da64d6db3bd3 ("io_uring: One wqe per wq")
Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
Link: https://lore.kernel.org/r/20240910171157.166423-3-felix.moessbauer@siemens.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>