Merge pull request #1711 from DonLakeFlyer/MavlinkFix

Remove old MAV_AUTOPILOT_PIXHAWK

src/uas/UAS.h

@@ -612,9 +612,6 @@ public:
         case MAV_AUTOPILOT_GENERIC:
             return "GENERIC";
             break;
-        case MAV_AUTOPILOT_PIXHAWK:
-            return "PIXHAWK";
-            break;
         case MAV_AUTOPILOT_SLUGS:
             return "SLUGS";
             break;
@@ -649,7 +646,7 @@ public:
             return "PX4";
             break;
         default:
-            return "";
+            return "UNKNOWN";
             break;
         }
     }