HID: udraw-ps3: Add support for the uDraw tablet for PS3

This adds support for the THQ uDraw tablet for the PS3, as
4 separate device nodes, so that user-space can easily consume
events coming from the hardware.

Note that the touchpad two-finger support is fairly unreliable,
and a right-click can only be achieved with a two-finger tap
with the two fingers slightly apart (about 1cm should be enough).

Tested-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>