This is in preparation for receiving XI2 touch events. The version change is necessary as the events aren't sent at all otherwise.
-- v2: winex11: Simplify XInput2 device valuator lookup. winex11: Always listen to XInput2 device changes events. winex11: Initialize XInput2 extension on every thread. winex11: Advertise XInput2 version 2.2 support. winex11: Process XInput2 events with QS_INPUT filter.