Put DEBUG ifdefs around prints in process_timestamps

packet-exchange/src/send_packet.c

@@ -244,8 +244,10 @@ static void process_timestamps(struct packet_timestamps *packet_ts) {
       struct timespec *stamp = (struct timespec *)CMSG_DATA(cmsg);
       packet_ts->kernel_leave = ts_to_uint(*stamp);
     } else {
+#ifdef DEBUG
       fprintf(stderr, "process_timestamps: level %d type %d", cmsg->cmsg_level,
               cmsg->cmsg_type);
+#endif
     }
   }
 }