Qt: Change settings dialogs to widgets/windows

Stops them breaking in Qt 6.6.

src/duckstation-qt/advancedsettingswidget.h

@@ -7,14 +7,14 @@
 
 #include "ui_advancedsettingswidget.h"
 
-class SettingsDialog;
+class SettingsWindow;
 
 class AdvancedSettingsWidget : public QWidget
 {
   Q_OBJECT
 
 public:
-  explicit AdvancedSettingsWidget(SettingsDialog* dialog, QWidget* parent);
+  explicit AdvancedSettingsWidget(SettingsWindow* dialog, QWidget* parent);
   ~AdvancedSettingsWidget();
 
 private:
@@ -47,7 +47,7 @@ private:
     };
   };
 
-  SettingsDialog* m_dialog;
+  SettingsWindow* m_dialog;
 
   Ui::AdvancedSettingsWidget m_ui;