Update legacy u-boot to swap a/b boot based on the script in partition 12.

This is roughly based on the old way that the "recovery" flavour did
things.  However, in this case we're not actually using the kernel
partition (partition 2), but still loading the kernel from the root
filesystem (/boot/vmlinux.uimg).  We just support swapping which
root filesystem we'll use.

BUG=chromium-os:15720
TEST=Ran image_to_live.sh and saw a/b switch.

Change-Id: I3319eda9a2b8197e3b4336c71cba776cca6de4e9
Reviewed-on: http://gerrit.chromium.org/gerrit/1492
Tested-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Nick Sanders <nsanders@chromium.org>
1 file changed