KVM: MMU: fix missing post sync audit

Add AUDIT_POST_SYNC audit for long mode shadow page

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 272e302..df465f6 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2540,6 +2540,7 @@
 		hpa_t root = vcpu->arch.mmu.root_hpa;
 		sp = page_header(root);
 		mmu_sync_children(vcpu, sp);
+		trace_kvm_mmu_audit(vcpu, AUDIT_POST_SYNC);
 		return;
 	}
 	for (i = 0; i < 4; ++i) {