Implements support for system level traces compatible with SEGGER
SystemView tool on top of ESP32 application tracing module.
That kind of traces can help to analyse program's behaviour.
SystemView can show timeline of tasks/ISRs execution, context switches,
statistics related to the CPUs' load distribution etc.
Also this commit adds useful feature to ESP32 application tracing module:
- Trace data buffering is implemented to handle temporary peaks of events load
- Implements application tracing module which allows to send arbitrary
data to host over JTAG. This feature is useful for analyzing
program modules behavior, dumping run-time application data etc.
- Implements printf-like logging functions on top of apptrace module.
This feature is a kind of semihosted printf functionality with lower
overhead and impact on system behaviour as compared to standard printf.
