esp_flash: fix the coredump issue

During coredump, dangerous-area-checking should be disabled, and cache
disabling should be replaced by a safer version.

Dangerous-area-checking used to be in the HAL, but it seems to be more
fit to os functions. So it's moved to os functions. Interfaces are
provided to switch between os functions during coredump.

components/spi_flash/include/esp_flash.h

@@ -45,6 +45,9 @@ typedef struct {
     /** Called after completing any flash operation. */
     esp_err_t (*end)(void *arg);
 
+    /** Called before any erase/write operations to check whether the region is limited by the OS */
+    esp_err_t (*region_protected)(void* arg, size_t start_addr, size_t size);
+
     /** Delay for at least 'ms' milliseconds. Called in between 'start' and 'end'. */
     esp_err_t (*delay_ms)(void *arg, unsigned ms);
 } esp_flash_os_functions_t;