"Node has no address family in common with server" when deploying a LXD VM on an IPv6-only bridge

[Christian Grabowski]

When trying to deploy a LXD VM on an IPv6-only bridge created by `lxd init`, I receive the error "Node has no address family in common with server" while the bridge is on the Rack Controller and was able to commission the VM successfully. It seems the issue lies in the section of node.start() that checks if both the boot rack controller and the deploying machine have common IP address families, in this case IPv6.