drm/msm/dp: Add sc8180x DP controllers

The sc8180x has 2 DP and 1 eDP controllers, add support for these to the
DP driver.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20211217002643.2305526-1-bjorn.andersson@linaro.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>