Use virt-who --print for getting Hypervisors data instead of Satellite

[mossicrue]

If custom facts of an hypervisor aren't available from Satellite, eg: hypervisors socket data are reported by virt-who but are stored only in candlepin DB and not stored in foreman DB / Satellite DB (BZ1638814), we can call virt-who --print to retrieve custom facts that aren't present via API.

virt-who --print returns a json containing an array of hypervisor dictionary which has in facts sub-dictionary the data we are looking for.

"facts": {
  "hypervisor.type": "VMware ESXi",
  "cpu.cpu_socket(s)": "4",
  "hypervisor.cluster": "cluster_name",
  "hypervisor.version": "6.5.0"
}

We can use cpu.cpu_socket(s) field to retrieve the number of sockets of an hypervisor and use this value as workaround of the solution I provided on issue #5.

[evgeni]

fixed in 3821d6a