Match on IPv6 routing header

--rt-type [!]type
    Match the type (numeric).

--rt-segsleft[!]num[:num]
    Match the `segments left' field (range).

--rt-len[!]length
    Match the length of this header

--rt-0-res
    Match the reserved field, too (type=0)

--rt-0-addrs ADDR[,ADDR...]
    Match type=0 addresses (list).

--rt-0-not-strict
    List of type=0 addresses is not a strict list.