x86: Move gds_ucode_mitigated() declaration to header

mainline inclusion
from mainline-v6.5-rc6
commit eb3515dc
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7XLNT
CVE: CVE-2022-40982

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb3515dc99c7c85f4170b50838136b2a193f8012



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

The declaration got placed in the .c file of the caller, but that
causes a warning for the definition:

arch/x86/kernel/cpu/bugs.c:682:6: error: no previous prototype for 'gds_ucode_mitigated' [-Werror=missing-prototypes]

Move it to a header where both sides can observe it instead.

Fixes: 81ac7e5d ("KVM: Add GDS_NO support to KVM")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Cc: stable@kernel.org
Link: https://lore.kernel.org/all/20230809130530.1913368-2-arnd%40kernel.org


Signed-off-by: Zeng Heng <zengheng4@huawei.com>