[libwnck] xutils: fix 'G_SIZEOF_LONG is not defined' warning

[Alberts Muktupāvels <muktupavels src gnome org>]

commit e4d7d6f0ab52cdb673e0534bfa9b64ece3c3181e
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Apr 27 13:28:44 2017 +0300

    xutils: fix 'G_SIZEOF_LONG is not defined' warning

 libwnck/xutils.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/libwnck/xutils.c b/libwnck/xutils.c
index 40ead7f..9bb1681 100644
--- a/libwnck/xutils.c
+++ b/libwnck/xutils.c
@@ -829,7 +829,7 @@ _wnck_xid_hash (gconstpointer v)
   gulong val = * (const gulong *) v;
 
   /* I'm not sure this works so well. */
-#if G_SIZEOF_LONG > 4
+#if GLIB_SIZEOF_LONG > 4
   return (guint) (val ^ (val >> 32));
 #else
   return val;