x86/Intel: don't probe CPUID faulting on family 0xf CPUs

These are known to not support the feature, so we can save ourselves
from emitting the resulting #GP fault recovery related message (which
might worry people looking at the logs).

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/cpu/intel.c
+++ b/xen/arch/x86/cpu/intel.c
@@ -204,7 +204,7 @@ static void __devinit init_intel(struct 
 		detect_ht(c);
 	}
 
-	if (smp_processor_id() == 0) {
+	if (c == &boot_cpu_data && c->x86 == 6) {
 		if (probe_intel_cpuid_faulting())
 			set_bit(X86_FEATURE_CPUID_FAULTING, c->x86_capability);
 	} else if (boot_cpu_has(X86_FEATURE_CPUID_FAULTING)) {