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