KVM: MMU: Set shadow pte atomically in mmu_pte_write_zap_pte()

Setting shadow page table entry should be set atomicly using set_shadow_pte().
Signed-off-by: NIzik Eidus <izike@qumranet.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

drivers/kvm/mmu.c

@@ -1088,7 +1088,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
 			mmu_page_remove_parent_pte(child, spte);
 		}
 	}
-	*spte = 0;
+	set_shadow_pte(spte, 0);
 	kvm_flush_remote_tlbs(vcpu->kvm);
 }