Works around bug reported on forums where any source file ending in *lock.c or *creat.c was being linked to IRAM. https://esp32.com/viewtopic.php?f=13&t=8909&p=37362#p37362 Also moves all related functionality to newlib component.
* Prevents section type conflict errors if (say) const & non-const data is put into the same section (ie with DRAM_ATTR) * Allows linker --gc-sections to remove unused custom sections