KVM: Free apic access page on vm destruction

Noticed by Marcelo Tosatti.
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/x86/kvm/x86.c

@@ -3853,6 +3853,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 	kfree(kvm->arch.vioapic);
 	kvm_free_vcpus(kvm);
 	kvm_free_physmem(kvm);
+	if (kvm->arch.apic_access_page)
+		put_page(kvm->arch.apic_access_page);
 	kfree(kvm);
 }