[media] Input: atmel_mxt_ts - add diagnostic data support for mXT1386

The mXT1386 family of chips have a different architecture which splits
the diagnostic data into 3 columns.

Signed-off-by: Nick Dyer <nick@shmanahar.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>