mtd1: 06400000 00040000 "kernel"
     ----------------------------------

It is obvious that we lost the truncated partition `rootfs` which should
be 824MiB in this case.

Also, forbid 0-sized partitions.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
¹