x86/cpu: Fix common cpuid faulting probing for AMD and Hygon

x86/cpu: Fix common cpuid faulting probing for AMD and Hygon

There is no MSR_INTEL_PLATFORM_INFO for AMD and Hygon families. Read
this MSR will stop the Xen initialization process in some Hygon
systems or produce GPF(0). So directly return false in the function
probe_cpuid_faulting() if !cpu_has_hypervisor.

Signed-off-by: Pu Wen <puwen@hygon.cn>
Acked-by: Jan Beulich <jbeulich@suse.com>
[Rebase over 0cd074144cb "x86/cpu: Renumber X86_VENDOR_* to form a bitmap"]
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>