sapAtmLLFOperStatus indicates whether or not the
underlying port is forced operationally 'down' due to the
service being operationally 'down' or an
sdpBindPwPeerStatusBits bit is set.
sapAtmLLFOperStatus is set to 'fault' when the
sapAtmLLFAdminStatus is set to 'up,' and either a
fault has occurred on the pseudo-wire, or the service is
down, otherwise sapAtmLLFOperStatus is set to 'clear.'