Revert "CHROMIUM: arm64: dts: mt8173-oak: remove panel's ddc-i2c-bus"

This reverts commit a233af7d9869556270a508947754c06ad9c216a9.

This commit causes the recovery flow stucks in the fb driver on the Elm platform.

BUG=chrome-os-partner:52432
TEST=build a recovery image and run the recvery flow on Elm rev0

Change-Id: Ia425ee6347a340061fbe041a019a7534265136b0
Reviewed-on: https://chromium-review.googlesource.com/340530
Commit-Ready: Paris Yeh <pyeh@chromium.org>
Tested-by: Milton Chiang <milton.chiang@mediatek.com>
Reviewed-by: Paris Yeh <pyeh@chromium.org>