commit 7d0b9349 upstream.

Several Samsung laptop models (SAMSUNG 870Z5E/880Z5E/680Z5E and
SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V) do not have a working
native backlight control interface so restore their acpi_videoX
interface.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=84221
Link: https://bugzilla.kernel.org/show_bug.cgi?id=84651
For SAMSUNG 870Z5E/880Z5E/680Z5E:
Reported-and-tested-by: Brent Saner <brent.saner@gmail.com>
Reported-by: Vitaliy Filippov <vitalif@yourcmc.ru>
Reported-by: Laszlo KREKACS <laszlo.krekacs.list@gmail.com>
For SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V:
Reported-by: Vladimir Perepechin <vovochka13@gmail.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>