When ESP32's flat build mode is selected with the external PSRAM
on USER_HEAP mode, the ROM strdup internally calls malloc which may
be mapped to a different heap than lib_free, causing cross-heap
allocation issues and system crashes.
This commit adds a new Kconfig option ESP32_DONT_USE_ROM_LIBC to
allow using NuttX libc instead of ROM newlib functions. When
USER_HEAP mode is selected, this option is automatically enabled.
Signed-off-by: Tiago Medicci Serrano <tiago.medicci@espressif.com>
36f07f5c44