arm64: dts: qcom: sm8550: enable DISPCC by default

Enable the Display Clock Controller by default in SoC DTSI so unused
clocks can be turned off.  It does not require any external resources,
so as core SoC component should be always available to boards.

Suggested-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230516154539.238655-1-krzysztof.kozlowski@linaro.org