[autotest] Disable weekly test of chameleon_dp and chameleon_hdmi on R38

Tests do not exist on R38.

BUG=chromium:427373
TEST=None

Change-Id: I82057761c232e1bb452a94942a1fffa1318d9516
Reviewed-on: https://chromium-review.googlesource.com/225509
Tested-by: Dan Shi <dshi@chromium.org>
Reviewed-by: Fang Deng <fdeng@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
1 file changed