virtio-input: fix segfault in virtio_input_hid_properties

commit 5cce173 introduced virtio-input segfault, This patch fixes it.

Signed-off-by: Lin Ma <lma@suse.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/hw/input/virtio-input-hid.c b/hw/input/virtio-input-hid.c
index 616a815..4d85dad 100644
--- a/hw/input/virtio-input-hid.c
+++ b/hw/input/virtio-input-hid.c
@@ -308,6 +308,7 @@
 static Property virtio_input_hid_properties[] = {
     DEFINE_PROP_STRING("display", VirtIOInputHID, display),
     DEFINE_PROP_UINT32("head", VirtIOInputHID, head, 0),
+    DEFINE_PROP_END_OF_LIST(),
 };
 
 static void virtio_input_hid_class_init(ObjectClass *klass, void *data)