arm64: dts: qcom: msm8996: add clocks to the MMCC device node

As we are converting this platform to use DT clock bindings, add clocks
and clock-names properties to the MMCC device tree node.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220617122922.769562-7-dmitry.baryshkov@linaro.org