BayTrail-based and newer Chromebooks describe their peripherals in ACPI;
unfortunately their description is not complete, and peripherals
drivers, such as driver for Atmel Touch controllers, has to resort to
DMI-matching to configure the peripherals properly. To avoid polluting
peripheral driver code, let's teach chromeos_laptop driver to supply
missing data via generic device properties.

Note we supply "compatible" string for Atmel peripherals not because it is
needed for matching devices and driver (matching is still done on ACPI HID
entries), but because peripherals driver will be using presence of
"compatible" property to determine if device properties have been attached
to the device, and fail to bind if they are absent.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Benson Leung <bleung@chromium.org>