arm64: dts: qcom: sdm845: align RPMh regulator nodes with bindings

Device node names should be generic and bindings expect certain pattern
for RPMh regulator nodes.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230127114347.235963-6-krzysztof.kozlowski@linaro.org