Port Scoped SR-IOV NUMA Affinity Policies

In some environments the server form factor is restricted, preventing PCI devices from being physically installed across all NUMA nodes on a server, e.g. high density blade/multi server systems or non standard form factor equipment. In the Ussuri release operators gained the flexibility to specify a VM-wide NUMA affinity policy via the flavor or image however in many cases different NICs have different constraint. This work builds on a previous feature introduced in the Ussuri release and extends the granularity to allow per neutron port NUMA affinity policies.