Add ArduSub firmware branding.

qgcresources.qrc

@@ -153,6 +153,7 @@
         <file alias="ArrowCW.svg">src/AutoPilotPlugins/Common/Images/ArrowCW.svg</file>
         <file alias="ArrowCCW.svg">src/AutoPilotPlugins/Common/Images/ArrowCCW.svg</file>
         <file alias="APM/BrandImage">src/FirmwarePlugin/APM/APMBrandImage.png</file>
+        <file alias="APM/BrandImageSub">src/FirmwarePlugin/APM/APMBrandImageSub.png</file>
         <file alias="PX4/BrandImage">src/FirmwarePlugin/PX4/PX4BrandImage.png</file>
     </qresource>
     <qresource prefix="/res">

src/FirmwarePlugin/APM/ArduSubFirmwarePlugin.h

@@ -76,6 +76,8 @@ public:
     bool supportsRadio(void);
 
     bool supportsJSButton(void);
+
+    QString brandImage(const Vehicle* vehicle) const { Q_UNUSED(vehicle); return QStringLiteral("/qmlimages/APM/BrandImageSub"); }
 };
 
 #endif