Allow plugins to be skipped at runtime (#7691)

Allows plugins (such as carla) to be skipped when not installed

include/PluginFactory.h

@@ -104,6 +104,8 @@ private:
 	QHash<QString, QString> m_errors;
 
 	static std::unique_ptr<PluginFactory> s_instance;
+
+	static void filterPlugins(QSet<QFileInfo>& files);
 };
 
 //Short-hand function