Add ACPI methods to the Wilco EC for controlling a privacy screen
on the device.
BUG=b:142237145, b:142656363
TEST=none
Change-Id: Ic3c136f9d2de90eeb3c9e468e4c7430ccf6dcc42
Signed-off-by: Mathew King <mathewk@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36044
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>