Update available flight modes for ArduSub.

src/FirmwarePlugin/APM/ArduSubFirmwarePlugin.cc

@@ -32,6 +32,7 @@ APMSubMode::APMSubMode(uint32_t mode, bool settable) :
     APMCustomMode(mode, settable)
 {
     QMap<uint32_t,QString> enumToString;
+    enumToString.insert(MANUAL, "Manual");
     enumToString.insert(STABILIZE, "Stabilize");
     enumToString.insert(ALT_HOLD,  "Depth Hold");
 
@@ -41,6 +42,7 @@ APMSubMode::APMSubMode(uint32_t mode, bool settable) :
 ArduSubFirmwarePlugin::ArduSubFirmwarePlugin(void)
 {
     QList<APMCustomMode> supportedFlightModes;
+    supportedFlightModes << APMSubMode(APMSubMode::MANUAL ,true);
     supportedFlightModes << APMSubMode(APMSubMode::STABILIZE ,true);
     supportedFlightModes << APMSubMode(APMSubMode::ALT_HOLD  ,true);
     setSupportedModes(supportedFlightModes);

src/FirmwarePlugin/APM/ArduSubFirmwarePlugin.h

@@ -50,9 +50,11 @@ public:
         RESERVED_14       = 14,
         RESERVED_15       = 15,
         RESERVED_16       = 16,
-        RESERVED_17       = 17
+        RESERVED_17       = 17,
+        RESERVED_18       = 18,
+        MANUAL            = 19
     };
-    static const int modeCount = 18;
+    static const int modeCount = 20;
 
     APMSubMode(uint32_t mode, bool settable);
 };