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>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 875b785..2e87296 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4245,7 +4245,8 @@
 
 	set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
 
-	r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx), THIS_MODULE);
+	r = kvm_init(&vmx_x86_ops, sizeof(struct vcpu_vmx),
+		     __alignof__(struct vcpu_vmx), THIS_MODULE);
 	if (r)
 		goto out3;