HID: hid-multitouch: add support for Unitec panels

This patch introduce support for Unitec panels.
This device has not been optimized in term of kernel processing
operations (default class), but it will work.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>