r0 = socket$inet_udp(0x2, 0x2, 0x0)
ioctl$sock_inet_SIOCDELRT(r0, 0x890b, &(0x7f00000002c0)={0x0, {0x2, 0x0, @private}, {0x2, 0x0, @private}, {0x2, 0x0, @multicast1}, 0x1e})