* introduce recovery (=initramfs) vs. production dual boot scheme
* make use of uImage.FIT (instead of FAT partition)
* generate images using build steps (instead of external scripts)
* simplify sysupgrade and config restore (thanks to uImage.FIT)
* make sure mmc devices are ordered persistently (set DT aliases)
This commit breaks sysupgrade from existing installations, you will
have to re-install using the sdcard.img.gz image.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>