parade/ps8640: disable mipi mcs

Disable ps8640 mipi mcs function to avoid recognizing the normal mipi dsi
signal as msc cmd.

BUG=chrome-os-partner:56346
BRANCH=none
TEST=build pass elm and show ui

Change-Id: I91c690fb1ff3bd9b5c1f227205829c914347cd30
Signed-off-by: Martin Roth <martinroth@chromium.org>
Original-Commit-Id: 4fd441b46300fea9f238b27c9c1cda4e9e53c80d
Original-Change-Id: I85b9f1e6677e4bf8ab1e30c2e69445079fff2d18
Original-Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/373219
Original-Commit-Ready: Daniel Kurtz <djkurtz@chromium.org>
Original-Tested-by: jitao shi <jitao.shi@mediatek.com>
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-on: https://review.coreboot.org/16365
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2 files changed