dt-bindings: msm/dp: Add SC8180x compatibles

The Qualcomm SC8180x has 2 DP controllers and 1 eDP controller, add
compatibles for these to the msm/dp binding.

Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211016221843.2167329-7-bjorn.andersson@linaro.org


Signed-off-by: Rob Clark <robdclark@chromium.org>