bridge: Do not unregister all PF_BRIDGE rtnl operations

Bridge fdb and link rtnl operations are registered in
core/rtnetlink.  Bridge mdb operations are registred
in bridge/mdb.  When removing bridge module, do not
unregister ALL PF_BRIDGE ops since that would remove
the ops from rtnetlink as well.  Do remove mdb ops when
bridge is destroyed.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc net/bridge/br_mdb.c
Simple merge

diff --cc net/bridge/br_multicast.c
Simple merge

diff --cc net/bridge/br_netlink.c
Simple merge

diff --cc net/bridge/br_private.h
Simple merge