io_uring: add missing item types for splice request

stable inclusion
from stable-v5.10.160
commit 75454b4bbfc7e6a4dd8338556f36ea9107ddf61a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6AUN9
CVE: CVE-2022-4696

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=75454b4bbfc7e6a4dd8338556f36ea9107ddf61a



--------------------------------

Splice is like read/write and should grab current->nsproxy, denoted by
IO_WQ_WORK_FILES as it refers to current->files as well

Signed-off-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
(cherry picked from commit 9a7973c3)