This is a basic driver for the Surface 3. I am not so sure it will work
with any firmwares as most values are encoded, but given that I only have
access to my current device with its firmware and I don't have the
datasheet, it should be OK for now.

The Surface Pen is not supported (if it is supposed to be). I'll work on
this when I get one.
Tested-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>