team: move netlink event notifiers after team_port_leave()

In team_port_del(), there is need to be do all the cleanup related
things first and netlink event notifiers should be called after that.
This fixes two problems:
team carrier is now correctly set (port is removed from list first)
mode can set option as changed in .port_leave op

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>