Add DMA lidar lite reader.

Change-Id: I8195ff2331029adcdb961b9925f43471cc6b08f9
diff --git a/y2018/control_loops/superstructure/superstructure.q b/y2018/control_loops/superstructure/superstructure.q
index 0da9d17..9bdabed 100644
--- a/y2018/control_loops/superstructure/superstructure.q
+++ b/y2018/control_loops/superstructure/superstructure.q
@@ -171,6 +171,9 @@
     // Value of the beambreak sensor detecting when the box has hit the frame
     // cutout.
     bool box_back_beambreak_triggered;
+
+    // Distance to the box in meters.
+    double box_distance;
   };
 
   message Output {