Merge branch 'feature/get_chip_ver' into 'master'

add API to get chip info

This change adds an API to get chip info, such as chip model, enabled capabilities, size of embedded flash, silicon revision.

Hello_world example is modified to print out the information about the chip. The example is also simplified by moving all code into the main task.

Ref TW12031.

See merge request !549

diff --cc components/esp32/include/esp_system.h
Simple merge

diff --cc components/esp32/system_api.c
Simple merge