dt-bindings: clock: add QCOM SM6375 display clock

Add device tree bindings for display clock controller for
Qualcomm Technology Inc's SM6375 SoC.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221115155808.10899-1-konrad.dybcio@linaro.org