arm64: dts: qcom: sdm845: Add missing RPMh power domain to GCC

GCC and it's GDSCs are under the RPMh CX power domain. So let's add the
missing RPMh power domain to the GCC node.

Fixes: 6d4cf750 ("arm64: dts: sdm845: Add minimal dts/dtsi files for sdm845 SoC and MTP")
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Co-developed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20230720054100.9940-4-manivannan.sadhasivam@linaro.org


Signed-off-by: Bjorn Andersson <andersson@kernel.org>