hal : properly clear thread instances during vts

hal VTS test cases opens and closes adev continuously for test case.
Battery Listener is initialized during adev_open but not properly deinitialized
during adev_close .
in battery_listener unregister all the reference which were registered during
init .

Change-Id: I9793f24f717ec760a79ee4316c227b25de30609e
2 files changed