See the previous patch for a long explanation.

TL;DR: the P52 and the t480s from Lenovo can't rely on I2C to fetch
the information, so we need it from PS/2.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>