Fix CARP when in use in a HyperV environment:
- Bump link state when stopping or starting the interface;
- Don't handle SIOCGIFADDR specially, similar to r277103.
This change is based on a previous revision from Andy Zhang
(Microsoft) who did the diagnostic work and many thanks to
them for their help in supporting the HyperV work.
PR: kern/187203
4d744c17ad