The value of tmnxL2tpLacMlpppBundleFwdTuId indicates the
LTS (L2TP Tunnel Stitching) tunnel ID if this bundle is associated
with PPP sessions that are stitched to another L2TP tunnel.
Otherwise, the value of tmnxL2tpLacMlpppBundleFwdTuId is equal to zero.