PIM using point-to-multipoint mode support for AutoVPN and Auto Discovery VPN

Protocol Independent Multicast (PIM) using point-to-multipoint (P2MP) mode supports AutoVPN and Auto Discovery VPN in which a new p2mp interface type is introduced for PIM. The p2mp interface tracks all PIM joins per neighbor to ensure that multicast forwarding or replication happens only to those neighbors that are in joined state. In addition, the PIM using point-to-multipoint mode supports chassis cluster mode.