spb-rs2/ipv4: show protocols all megabit

megabit BGP --- down 19:04:35.467

Description:    megabit/57864/AS-MEGABIT
  BGP state:          Down
    Neighbor address: 185.1.152.213
    Neighbor AS:      57864
    Local AS:         50817
  Channel ipv4
    State:          DOWN
    Table:          rib4
    Preference:     100
    Input filter:   (unnamed)
    Output filter:  (unnamed)
    Import limit:   5000
      Action:       disable