modify hup to use a boot image and a main image

[ycardaillac]

hostapp-update -i -b

The idea is that the boot files are in a separated image and are extracted from there directly into a directory.
The rest of hup is the same.

Project: https://balena.fibery.io/Work/Project/Deduplicate-kernel-on-balenaOS-rootfs-2300

Change-type: minor

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  • Covered in automated test suite
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[flowzone-app]

Website deployed to CF Pages, 👀 preview link https://ebe0b46e.balena-os.pages.dev