refs #618, clang fixes

* use own default constructor error: default initialization of an object of const type 'const BlackMisc::CIcon' without a user-provided default constructor static const CIcon empty;
* same for CDbOwnModelsComponent()
* fixed guard

src/blackgui/components/data/lastselections.h

@@ -35,6 +35,9 @@ namespace BlackGui
                     IndexLastSimulator = BlackMisc::CPropertyIndex::GlobalIndexCDbOwnModelsComponent
                 };
 
+                //! Constructor
+                CDbOwnModelsComponent() {}
+
                 //! Simulator last selected
                 const BlackMisc::Simulation::CSimulatorInfo &getLastSimulatorSelection() const { return m_simulator; }
 

src/blackmisc/icon.h

@@ -23,11 +23,7 @@
 namespace BlackMisc
 {
     class CIcon;
-
+    namespace PhysicalQuantities { class CAngle; }
-    namespace PhysicalQuantities
-    {
-        class CAngle;
-    }
 
     namespace Mixin
     {
@@ -73,7 +69,7 @@ namespace BlackMisc
     {
     public:
         //! Default constructor.
-        CIcon() = default;
+        CIcon() {}
 
         //! Constructor.
         CIcon(CIcons::IconIndex index, const QString &descriptiveText);

src/blackmisc/simulation/aircraftmodelsetloader.h

@@ -10,7 +10,7 @@
 //! \file
 
 #ifndef BLACKMISC_SIMULATION_AIRCRAFTMODELSETLOADER_H
-#define BLACKMISC_SIMULATION_AIRCRAFTMODESETLLOADER_H
+#define BLACKMISC_SIMULATION_AIRCRAFTMODELSETLOADER_H
 
 #include "blackmisc/blackmiscexport.h"
 #include "blackmisc/simulation/aircraftmodellist.h"