ARM: dts: qcom: msm8960: drop useless rpm regulators node

ARM: dts: qcom: msm8960: drop useless rpm regulators node

The set of regulators available over the RPM requests is not a property
of the SoC. The only msm8960 board file (qcom-msm8960-cdp) also defines
this node together with the compatible string. Drop the useless device
node.

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230928110309.1212221-32-dmitry.baryshkov@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>