i386/cpu: Consolidate the helper to get Host's vendor

Extend host_cpu_vendor_fms() to help more cases to get Host's vendor
information.

Cc: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250410075619.145792-1-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2 files changed