gfio: add check for unnecessary g_thread_init() call

Annoying gtk likes to spew annoying deprecated warnings.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/gfio.c b/gfio.c
index 185dbd5..65302e6 100644
--- a/gfio.c
+++ b/gfio.c
@@ -1677,8 +1677,11 @@
 	 * Without it, the update that happens in gfio_update_thread_status
 	 * doesn't really happen in a timely fashion, you need expose events
 	 */
+#if !GTK_CHECK_VERSION(2, 24, 0)
 	if (!g_thread_supported())
 		g_thread_init(NULL);
+#endif
+
 	gdk_threads_init();
 
 	gtk_init(argc, argv);