refactor(plat/arm): update NV flags on image load/authentication failure

Erasing the FIP TOC header present in a flash is replaced by updating NV
flags with an error code on image load/authentication failure.
BL1 component uses these NV flags to detect whether a firmware update is
needed or not.
These NV flags get cleared once the firmware update gets completed.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I6232a0db07c89b2373b7b9d28acd37df6203d914
2 files changed