Skip deprecated g_type_init() for GLib 2.36

From Glib doc [link](https://developer.gnome.org/gobject/unstable/gobject-Type-Information.html#g-type-init) :
> g_type_init has been deprecated since version 2.36 and should not be used in newly-written code.
> the type system is now initialised automatically

Any review is welcome!