arm64: dts: qcom: pmk8350: Specify PBS register for PON

PMK8350 is the first PMIC to require both HLOS and PBS registers for
PON to function properly (at least in theory, sm8350 sees no change).
The support for it on the driver side has been added long ago,
but it has never been wired up. Do so.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221115132626.7465-1-konrad.dybcio@linaro.org