arm64: dts: qcom: sa8295-adp: Enable DP instances

The SA8295P ADP has, among other interfaces, six MiniDP connectors which
are connected to MDSS0 DP2 and DP3, and MDSS1 DP0 through DP3.

Enable Display Clock controllers, MDSS instanced, MDPs, DP controllers,
DP PHYs and link them all together.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230111035906.2975494-4-quic_bjorande@quicinc.com