Allow to dynamically grow the amount of fibs in each vnet.
This change alters current behaviour: currently, if one defines ROUTETABLES > 1 in the kernel config, each vnet will be created with the number of fibs defined in the kernel config. This change sets default number of fibs in the vnet to be always 1.
Dynamic net.fibs is not compatible with net.add_addr_allfibs. The plan is to deprecate the latter and make the net.add_addr_allfibs=0 default behaviour.
- Update rt_numfibs to V_rt_numfibs (60 occasions).
- Add interface fib handler, similar to vnet fib handler
- Deprecate net.add_addr_allfibs