fwu: DeveloperBox: add support for FWU

Add code to support FWU_MULTI_BANK_UPDATE.
The platform does not have gpt-partition storage for
Banks and MetaData, rather it used SPI-NOR backed
mtd regions for the purpose.

Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
6 files changed