Input: atmel_mxt_ts - add generic platform data for Chromebooks

Apparently people are installing generic Linux distributions not only on
Pixels but also on other Chromebooks. Unfortunately on all of them Atmel
parts assigned names ATML0000 and ATML0001, and do not carry any other
configuration data. So let's create generic instance of platform data that
should cover most of them (we assume that they will not be using T100
objects, since with those Google mapped BTN_LEFT onto a different GPIO, so
slightly different keymap would be needed, but I think we used parts with
T100 on ARM devices where we thankfully have DTS and can describe the
devices better).

Tested-by: Rich K <rgkirch@gmail.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>