Expose OpenFabrics interop

[HadrienG2]

Expose hwloc interoperability with the OpenFabrics networking library (infiniband etc), add suitable feature+cfg+doc(cfg)+cfg(doc): https://hwloc.readthedocs.io/en/v2.9/group__hwlocality__openfabrics.html

[HadrienG2]

I don't have access to a system that has a working OpenFabrics setup, contributions from people who have access to one and are interested in this feature would be appreciated.