x86: Add insn_decode_kernel()

stable inclusion
from stable-v5.10.133
commit 9a6471666b7387ba0af70d504fe1602cc3d3e5b2
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5PTAS
CVE: CVE-2022-29900,CVE-2022-23816,CVE-2022-29901

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9a6471666b7387ba0af70d504fe1602cc3d3e5b2



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

This was done by commit 52fa82c2
upstream, but this backport avoids changing all callers of the
old decoder API.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lin Yujun <linyujun809@huawei.com>
Reviewed-by: Zhang Jianhua <chris.zjh@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>