[mutter] x11: fix compilation if 'libwacom=false'

[Carlos Garnacho <carlosg src gnome org>]

commit a8f6cada883eda2a34e6478a53e2fb7c392d98b7
Author: Christian Rauch <Rauch Christian gmx de>
Date:   Tue Mar 31 21:28:44 2020 +0100

    x11: fix compilation if 'libwacom=false'
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1168

 src/backends/x11/meta-input-device-x11.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/backends/x11/meta-input-device-x11.c b/src/backends/x11/meta-input-device-x11.c
index 480acd83e..2406c34d7 100644
--- a/src/backends/x11/meta-input-device-x11.c
+++ b/src/backends/x11/meta-input-device-x11.c
@@ -122,9 +122,9 @@ meta_input_device_x11_is_grouped (ClutterInputDevice *device,
 static void
 meta_input_device_x11_finalize (GObject *object)
 {
-#ifdef HAVE_LIBWACOM
   MetaInputDeviceX11 *device_xi2 = META_INPUT_DEVICE_X11 (object);
 
+#ifdef HAVE_LIBWACOM
   if (device_xi2->group_modes)
     g_array_unref (device_xi2->group_modes);
 #endif