esp_system: removed repeated interrupt allocator code and moved common code to esp_system
xtens: moved xtensa specific code from freertos to the xtensa component
hal/interrupt_controller: added interrupt controller hal and ll files
docs: update the doxyfile with new location of esp_itr_alloc.h file
xtensa: fixed dangerous relocation problem after moving xtensa interrupt files out of freertos
docs: removed Xtensa reference from intr_allocator api-reference
xtensa: pushed the interrupt function that manages non iram interrupts to the xtensa layer
esp_system/test: fixed platform dependent setting for intr_allocator tests
hal: rename the functions used to manage non iram interrupt mask.
- Introduce system time function and concept of system time provider.
esp_timer is system time provider when present.
- Set the reference point for system time, g_startup_time.
- Use the system time functions in newlib instead of calling esp_timer
functions directly
