ACPI: video: Use native backlight on Lenovo E41-25/45

ACPI backlight control doesn't work on 2 Lenovo E41 laptops.
So force to use native backlight control on them.

Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>