Comment 1 for bug 2055347

MAAS explicitly checks if the passed k_g sting is 20 characters here: https://git.launchpad.net/maas/tree/src/maasserver/forms/settings.py#n931

Since the ipmitool allows hex-encoded input which will be longer than 20 characters and still resolve to 20 bytes, this validation needs to be fixed (either removed or made equivalent to what the ipmitool does).