More Chrono test fixes

* Timer test - handle removal of Timer(ticker_data_t *)
* Timer test - use Chrono, don't test deprecated methods
* Kernel tick count test - TEST_ASSERT_WITHIN -> TEST_ASSERT_INT_WITHIN
* Mutex test - fix up Chrono changes
* SysTimer test - adapt to SysTimer Chrono changes
* Thread test - use Chrono
* SysTimer - devirtualize destructor

Author: kjbracey