We can do away with a bunch of hacks now, but we’ll keep them around for a
little while to make updates easier (i.e. to boot with old and new gokr-packer
versions, just in case people don’t update both at the same time).
This is useful when the network doesn’t come up correctly: you can connect a
network cable between your computer and the gokrazy machine, press <ENTER> on
the serial console and connect to gokrazy via its IPv6 link-local address (to
find the address, use ping6 ff02::1%eth0).
