ARM: dts: msm: Add ADC channel nodes

Add thermistor channels that are connected and read from
PMA8084 VADC. Channel nodes are added to ADC_TM for
recurring measurements.

Change-Id: I5dcd2a7fc7ef03cf9d7d56f8c3142005143585d5
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>