arm64: dts: qcom: msm8996: mark apcs as clock provider

Now as we added the APCS clock controller support, mark apcs device as
clock provider by adding #clock-cells property.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230111191634.2509616-1-dmitry.baryshkov@linaro.org