The state of this interface wrt DF-Election wrt this RP.
unknown (0) indicates that there is no election state
on the interface.
dfOffer (1) indicates the initial election state in
which the winner offers its metrics thinking it might
eventually become winner.
dfLose (2) indicates the state in which the router
knows that there either is a different election winner
or that no router on the link has a path to the RP.
dfWinner (3) indicates the router is the acting DF
without any contest.
dfBackoff (4) indicates the router is the acting DF but
another router has made a bid to take over.