resp_addr_get_rrset
struct ub_packed_rrset_key* resp_addr_get_rrset(struct resp_addr* addr);
struct ub_packed_rrset_key* resp_addr_get_rrset(struct resp_addr* addr);
unit_assert(resp_addr_get_rrset(node) == NULL);
unit_assert((rrs = resp_addr_get_rrset(node)));