thermalservice: Add ThermalService java interfaces

Binder service ThermalService broadcasts thermal events to registered
listeners.

Test: manual: marlin with modified thermal-engine.conf and temporary
      java thermal event listener
Bug: 30982366
Change-Id: I11f7fd18feff3b9af0eecc3fd3a13d54c0b97ff0
(cherry picked from commit dd05582e)