Add hook to generate ACPI methods in SSDT for screen backlight control.
To make use of this, individual boards will need to
include default_brightness_levels.asl in their dsdt, as
well as add 'register "gfx" = "GMA_STATIC_DISPLAYS(0)"' to
their devicetree.
Change-Id: I0adccc6c8bee71d3c1b7840518308c8dc8ea2d81
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39943
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>