io_uring: drop any code related to SCM_RIGHTS

stable inclusion
from stable-v5.10.214
commit a6771f343af90a25f3a14911634562bb5621df02
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9P06W
CVE: CVE-2023-52656

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a6771f343af90a25f3a14911634562bb5621df02



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Commit 6e5e6d274956305f1fc0340522b38f5f5be74bdb upstream.

This is dead code after we dropped support for passing io_uring fds
over SCM_RIGHTS, get rid of it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Conflicts:
	io_uring/io_uring.c
	fs/io_uring.c
Signed-off-by: Zizhi Wo <wozizhi@huawei.com>