thermal: adc-tm: Add ADC_TM driver snapshot

ADC_TM peripheral is used by client to set thresholds on channels
supported by VADC and send notification once set thresholds are
crossed. The driver registers thermistors used for thermal
mitigation with of_thermal to allow thermal driver to set
thresholds and receive notification through thermal sysfs.

This is a snapshot of the driver taken from msm-4.19 as of commit
f94ba33e3b90 ("Merge "usb: dwc3-msm: Fix GDSC collapse in host mode
bus suspend").

Change-Id: I9211552317955c503b7287876e11cd161c37f706
Signed-off-by: Jishnu Prakash <jprakash@codeaurora.org>