esp_secure_boot_permanently_enable() function

Enable secure boot V1 if it is not already enabled. @important If this function succeeds, secure boot V1 is permanently enabled on the chip via efuse. @important This function is intended to be called from bootloader code only. @important In case of Secure Boot V1, this will enable r/w protection of secure boot key on EFUSE, therefore it is to be ensured that esp_secure_boot_generate_digest() is called before this .If secure boot is not yet enabled for bootloader, this will 1) enable R/W protection of secure boot key on EFUSE 2) enable secure boot by blowing the EFUSE_RD_ABS_DONE_0 efuse. This function does not verify secure boot of the bootloader (the ROM bootloader does this.) Will fail if efuses have been part-burned in a way that indicates secure boot should not or could not be correctly enabled.