Load P3D 64 bit SimConnect shared library at runtime

This aligns the behavior and concept with the 32 bit FSX version. SimConnect
is loaded at runtime, depending on the version being selected.
It also adds a featuren to change the P3D SimConnect version at runtime by
unloading the previous and loading a new one.

ref T349

src/plugins/simulator/fsxcommon/simconnectsymbols.h

@@ -12,9 +12,30 @@
 #ifndef BLACKSIMPLUGIN_FSXCOMMON_SIMCONNECTSYMBOLS_H
 #define BLACKSIMPLUGIN_FSXCOMMON_SIMCONNECTSYMBOLS_H
 
-//! Load and resolve SimConnect.
+#include <QtGlobal>
+
+#ifdef Q_OS_WIN64
+
+enum P3DSimConnectVersion
+{
+    P3DSimConnectv40,
+    P3DSimConnectv41,
+    P3DSimConnectv42,
+    P3DSimConnectv43
+};
+
+//! Load and resolve versioned P3D SimConnect.
+//! If a another version was already loaded previously, it won't unload it.
+//! You have to call /sa unloadSimConnect() before.
+bool loadAndResolveP3DSimConnect(P3DSimConnectVersion version);
+
+#else
+
+//! Load and resolve FSX SimConnect.
 //! \param manifestProbing  Set to true if you want to try loading from the assembly cache with manifests.
 //!                         Otherwise the library in the bin folder will be loaded.
-bool loadAndResolveSimConnect(bool manifestProbing);
+bool loadAndResolveFsxSimConnect(bool manifestProbing);
+
+#endif
 
 #endif // guard