This patch changes all uses of GDK_DEPRECATED(_FOR) in gdk headers
by the versioned variants, GDK_DEPRECATED_IN_3_x(_FOR). At the same
time, we add GDK_AVAILABLE_IN_3_x annotations for all API additions
in 3.2 and 3.4.
This function can be used to find out the XInput2 device ID
behind a GdkDevice, mostly useful when you need to interact
with say Clutter, or raw libXi calls.