IF_ADDR_UNLOCK() across network device drivers when accessing the
per-interface multicast address list, if_multiaddrs. This will
allow us to change the locking strategy without affecting our driver
programming interface or binary interface.
For two wireless drivers, remove unnecessary locking, since they
don't actually access the multicast address list.
Approved by: re (kib)
MFC after: 6 weeks
level. The distinction was artificial. Some more movement around the
deck charis is likely depending on the fallout from this one.
Paths were corrected after the svn mv. Hope that's OK.