tll-rs2/ipv4: show protocols all smartcenter

smartcenter BGP --- start 2021-11-17 Passive Error: Link down

Description:    smartcenter/48763/as-smartcentr
  BGP state:          Passive
    Neighbor address: 37.9.49.107
    Neighbor AS:      48763
    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