Updates and bugfixes:
- Disable Arm Standard C library mutex acquire/release when using stdio streams from interrupt
- Corrected osThreadGetState to return osThreadError when called for a thread previously terminated with osThreadTerminate
- Corrected osEventFlagsSet return value when called from ISR
- Corrected osEventFlagsWait to return osFlagsErrorParameter when called from ISR with non-zero timeout
- Corrected osTimerStart to return osErrorParameter when ticks argument equals zero
- Corrected SysTick_Handler and osKernelGetSysTimerCount to cope with tickless idle implementation
- Re-enable interrupts after mutex create in C lib stream protection initialization