ARM: dts: msm: Add ADC nodes for sdxpoorwills

Support clients to read vph_pwr, thermistor channels
such as MDM case therm, ambient therm, PA therms.

Change-Id: I2fd4ec002d35905ee53e29aadf019bfbae784fed
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>