KVM: selftests: Use this_cpu_has() in CR4/CPUID sync test

Use this_cpu_has() to query OSXSAVE from the L1 guest in the CR4=>CPUID
sync test.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-34-seanjc@google.com

tools/testing/selftests/kvm/include/x86_64/processor.h

@@ -160,9 +160,6 @@ struct kvm_x86_cpu_feature {
 #define X86_FEATURE_KVM_HC_MAP_GPA_RANGE	KVM_X86_CPU_FEATURE(0x40000001, 0, EAX, 16)
 #define X86_FEATURE_KVM_MIGRATION_CONTROL	KVM_X86_CPU_FEATURE(0x40000001, 0, EAX, 17)
 
-/* CPUID.1.ECX */
-#define CPUID_OSXSAVE		(1ul << 27)
-
 /* Page table bitfield declarations */
 #define PTE_PRESENT_MASK        BIT_ULL(0)
 #define PTE_WRITABLE_MASK       BIT_ULL(1)

tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c

@@ -21,19 +21,9 @@
 
 static inline bool cr4_cpuid_is_sync(void)
 {
-	int func, subfunc;
-	uint32_t eax, ebx, ecx, edx;
-	uint64_t cr4;
-
-	func = 0x1;
-	subfunc = 0x0;
-	__asm__ __volatile__("cpuid"
-			     : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
-			     : "a"(func), "c"(subfunc));
-
-	cr4 = get_cr4();
+	uint64_t cr4 = get_cr4();
 
-	return (!!(ecx & CPUID_OSXSAVE)) == (!!(cr4 & X86_CR4_OSXSAVE));
+	return (this_cpu_has(X86_FEATURE_OSXSAVE) == !!(cr4 & X86_CR4_OSXSAVE));
 }
 
 static void guest_code(void)