mpx: adding QueryPointer request and reply adjusting names of requests to Xlib compatible naming (xMPX*** instead of mpx***)
Some renaming and cleaning up in extinit.c MPXLastEvent added Xi: ShouldFreeInputMask() from XI is not static any more, used in mpx dix: GetPointerEvents() allocates MPX event for MPX devices. DeliverDeviceEvents() caters for MPX devices.