PF_RT_FLAGS
snl_add_msg_attr_u8(nw, PF_RT_FLAGS, r->flags);
{ .type = PF_RT_FLAGS, .off = _OUT(r.flags), .cb = snl_attr_get_uint8 },
nlattr_add_u8(nw, PF_RT_FLAGS, rule->flags);
{ .type = PF_RT_FLAGS, .off = _OUT(flags), .cb = nlattr_get_uint8 },