Adds multitouch support for the Gametel Android game controller.

The multitouch events are emulated by the Gametel device. Each physical button
is configured to generate a MT event on a specific coordinate. This seems to be
the only way for us to support Android games that doesn't support HID gamepads.
It is possible to inject MT events at Android level, but this requires root on
the phone.
Signed-off-by: Andreas Nielsen <eas@svep.se>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>