dt-bindings: thermal: qcom: add PMIC5 Gen2 ADC_TM bindings

Add documentation for PMIC5 Gen2 ADC_TM peripheral.
It is used for monitoring ADC channel thresholds for PMIC7-type
PMICs. It is present on PMK8350, like PMIC7 ADC and can be used
to monitor up to 8 ADC channels, from any of the PMIC7 PMICs
on a target, through PBS(Programmable Boot Sequence).

Signed-off-by: Jishnu Prakash <quic_jprakash@quicinc.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1648991869-20899-2-git-send-email-quic_jprakash@quicinc.com


Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>