Add ACPI code to enable the backlight when we enter the OS.
BUG=b:184198808
TEST=Backlight enabled in the OS
Signed-off-by: Martin Roth <martinroth@chromium.org>
Change-Id: I3e0a6c06120ac5abf0a0d82494e03d9cf80c1f8c
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52113
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>