bonding: remove "port-moved" state that was never implemented

LACP state-machine defines "port-moved" state when the same ActorSystemID
and Port are seen in a LACPDU received on different port. The state is
never set since it's not implemented. However the state-machine attempts
to clear that state occasionally. LACP state machine is already complicated
and since this state is not implemented, removing it's checks makes the
state-machine little simpler.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>