io_uring: add missing item types for various requests

Any read/write should grab current->nsproxy, denoted by IO_WQ_WORK_FILES
as it refers to current->files as well, and connect and recv/recvmsg,
send/sendmsg should grab current->fs which is denoted by IO_WQ_WORK_FS.

No upstream commit exists for this issue.

Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>