KVM: selftests: Use vcpu_get_cpuid_entry() in CPUID test

Use vcpu_get_cpuid_entry() instead of an open coded equivalent in the
CPUID test.

No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-28-seanjc@google.com

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

@@ -146,7 +146,6 @@ struct kvm_cpuid2 *vcpu_alloc_cpuid(struct kvm_vm *vm, vm_vaddr_t *p_gva, struct
 
 static void set_cpuid_after_run(struct kvm_vcpu *vcpu)
 {
-	struct kvm_cpuid2 *cpuid = vcpu->cpuid;
 	struct kvm_cpuid_entry2 *ent;
 	int rc;
 	u32 eax, ebx, x;
@@ -156,7 +155,7 @@ static void set_cpuid_after_run(struct kvm_vcpu *vcpu)
 	TEST_ASSERT(!rc, "Setting unmodified CPUID after KVM_RUN failed: %d", rc);
 
 	/* Changing CPU features is forbidden */
-	ent = get_cpuid_entry(cpuid, 0x7, 0);
+	ent = vcpu_get_cpuid_entry(vcpu, 0x7);
 	ebx = ent->ebx;
 	ent->ebx--;
 	rc = __vcpu_set_cpuid(vcpu);
@@ -164,7 +163,7 @@ static void set_cpuid_after_run(struct kvm_vcpu *vcpu)
 	ent->ebx = ebx;
 
 	/* Changing MAXPHYADDR is forbidden */
-	ent = get_cpuid_entry(cpuid, 0x80000008, 0);
+	ent = vcpu_get_cpuid_entry(vcpu, 0x80000008);
 	eax = ent->eax;
 	x = eax & 0xff;
 	ent->eax = (eax & ~0xffu) | (x - 1);