arm/dt: msm8610: Add ADC_TM node

ADC_TM is used for performing recurring channel measurement.
Clients include thermistors such as batt_therm, thermal nodes
and die_temp.

Change-Id: I8f161e6ab511eb294c72cb30964f83be30480d0a
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>