tll-rs2/ipv4: show protocols all cdcua2

cdcua2 BGP --- start 2021-09-15 Passive Error: Link down

Description:    cdcua2/49588/AS-SDS
  BGP state:          Passive
    Neighbor address: 37.9.49.97
    Neighbor AS:      49588
    Local AS:         57936
    Last error:       Error: Link down
  Channel ipv4
    State:          DOWN
    Table:          master4
    Preference:     100
    Input filter:   (unnamed)
    Output filter:  (unnamed)
    Import limit:   5000
      Action:       disable