KVM: Let vcpu structure alignment be determined at runtime

vmx and svm vcpus have different contents and therefore may have different
alignmment requirements.  Let each specify its required alignment.

Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/svm.c

@@ -3319,7 +3319,7 @@ static struct kvm_x86_ops svm_x86_ops = {
 static int __init svm_init(void)
 {
 	return kvm_init(&svm_x86_ops, sizeof(struct vcpu_svm),
-			      THIS_MODULE);
+			__alignof__(struct vcpu_svm), THIS_MODULE);
 }
 
 static void __exit svm_exit(void)