KVM: selftests: make hyperv_cpuid test pass on AMD

Enlightened VMCS is only supported on Intel CPUs but the test shouldn't
fail completely.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c

@@ -141,7 +141,13 @@ int main(int argc, char *argv[])
 
 	free(hv_cpuid_entries);
 
-	vcpu_ioctl(vm, VCPU_ID, KVM_ENABLE_CAP, &enable_evmcs_cap);
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_ENABLE_CAP, &enable_evmcs_cap);
+
+	if (rv) {
+		fprintf(stderr,
+			"Enlightened VMCS is unsupported, skip related test\n");
+		goto vm_free;
+	}
 
 	hv_cpuid_entries = kvm_get_supported_hv_cpuid(vm);
 	if (!hv_cpuid_entries)
@@ -151,6 +157,7 @@ int main(int argc, char *argv[])
 
 	free(hv_cpuid_entries);
 
+vm_free:
 	kvm_vm_free(vm);
 
 	return 0;