core/ipv4: show protocols all NETSHELTER_KLEYREX_V6

NETSHELTER_KLEYREX_V6 BGP --- start 2021-07-12 Active Socket: Connection closed

Description:    Netshelter Transit IPv6 at Kleyrex
  BGP state:          Active
    Neighbor address: 2001:7f8:33::a104:1047:1
    Neighbor AS:      41047
    Local AS:         213127
    Connect delay:    0.003/5
    Last error:       Socket: Connection closed
  Channel ipv6
    State:          DOWN
    Table:          master6
    Preference:     100
    Input filter:   do_not_import_own_prefix
    Output filter:  export_v6_rule