Re-evalute sources used for VM network interfaces gathering

[Venefilyn]

We discussed this a bit in #2303 and Matrix. In short, do we actively care about getting IPs from all the sources possible? Currently for each interface we fetch the IP from agent, lease, and arp. But we might as well just see if there is an IP on one source, if so take that, if not then check the other source

E.g.

flowchart TB
  cm[Cockpit Machines]-->|Search source for IPs| agent[Check agent]
  agent-->|Has IPs| show[Show source IPs]
  agent-->|No IP found| lease[Check lease]
  lease-->|Has IPs| show
  lease-->|No IP found| arp[Check arp]
  arp-->|Has IPs| show
  arp-->|No IP found| na[Show empty state]

Loading

VS the current implementation which takes from all sources

flowchart TB
  cm[Cockpit Machines]-->|Search source for IPs| agent[Check agent]
  agent-->|Has IPs| lease[Check lease]
  agent-->|No IP found| lease
  lease-->|Has IPs| arp[Check arp]
  lease-->|No IP found| arp
  arp-->|Has IPs| filter(Filter unique entries)
  filter-->show[Show all source IPs]
  arp-->|No IP found| na[Show empty state]

Loading