[PATCH 01/10] add habv4 support for i.MX6

[Marc Kleine-Budde]

Hello,

this series first cleans up the imx-image generation process. Then support for
HABv4 signed images is added. The last patch add code to decode HAB events,
which is usefull during development.

Tested on $CUSTOMER's i.MX6 solo.

cheers,
Marc