Use dns addresses for networkd configuration

[corest]

Required for this giantswarm/k8s-kvm#28

[xh3b4sd]

That should do it in general. I was just wondering about the consistency. This here is so consistent and is weird because the kvm-operator is anyway about the kvm provider.

[corest]

It is specific for onprem as we are configuring static networking for qemu node, which is unable to retrieve configuration with ignition and dhcp. Added configuration (https://github.com/giantswarm/installations/blob/master/geckon/draughtsman-configmap-values.yaml#L36) doesn't even exist for cloud providers

[xh3b4sd]

The installations repo is fine. There we need the distinction. Here we are in the kvm-operator. The operator having a flag ala provider.kvm is funny, because it is the kvm-operator. That is what I meant.

[corest]

Ah, got it. Just tried to keep configuration consistent with installation structure. But that is a questionable approach. Dropped Provider.KVM part