spec.loadBalancerIP always fail for ipv6

[uablrek]

An unnecessary To4() here causes specifying a loadBalancerIP to fail always for ipv6.

metallb version: v0.7.2

[uablrek]

No rush there is an issue in k8s as well (sigh...).

[danderson]

Thanks for the report! As you can tell, ipv6 support is not tested right now :(. I'm working on it, but I expect more gremlins like this are hiding in the code...