Lenovo Yoga Book uses PWM2 for controlling keyboard backlight but this
device is hidden in the DSDT in Windows version of notebook (if OSID == 1).
Make this device always present for this notebook.
Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>