- When flash encryption is enable to support reading a partition that is not
marked as "encrypted", the `esp_partition_read()` API of bootloader build
should be redirected to the `bootloader_flash_read()` API.
- When esp_parition_find_first() is called with the partition label provided
as NULL by the bootloader, allowing matching to the first partition that matches
partition_type and partition_subtype as done in the app variant.
