arm64: dts: qcom: sc8280xp-x13s: Add PM8280_{1/2} ADC_TM5 channels

Add ADC_TM5 channels of PM8280_{1/2} for monitoring the temperature from
external thermistors connected to AMUX pins. The temperature measurements
are collected from the PMK8280's VADC channels that expose the
measurements from secondary PMICs PM8280_{1/2}.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221103095810.64606-12-manivannan.sadhasivam@linaro.org