Workaround libc can be moved to flash thanks to KConfig macros. However, the following functions: `itoa`, `memcmp`, `memcpy`, `memset`, `strcat`, `strcmp`, and `strlen` are always kept it in IRAM.
Closes https://github.com/espressif/esp-idf/issues/7007 Closes https://github.com/espressif/esp-idf/issues/6715 Closes https://github.com/espressif/esp-idf/issues/3781 Closes https://github.com/espressif/esp-idf/issues/2566