intel/amenia: Enable touchscreen in ACPI

Add support for Elan touchscreen on I2C3 for amenia

BUG=None
TEST=Boot to Chromium OS and verify if touchscreen is working.

Change-Id: Ic75bef0e5878bd5b8c0d727400679663d9f591e3
Signed-off-by: Freddy Paul <freddy.paul@intel.com>
Reviewed-on: https://review.coreboot.org/14768
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed