main: Always remove the frameless window flag when restoring UI state

For unknown reasons, this flag may persist after the application has been closed.
Removing this flag when restoring the UI state ensures that a frameless window will not be shown on startup.

src/yuzu/main.cpp

@@ -1052,8 +1052,10 @@ void GMainWindow::SetDefaultUIGeometry() {
 }
 
 void GMainWindow::RestoreUIState() {
+    setWindowFlags(windowFlags() & ~Qt::FramelessWindowHint);
     restoreGeometry(UISettings::values.geometry);
     restoreState(UISettings::values.state);
+    render_window->setWindowFlags(render_window->windowFlags() & ~Qt::FramelessWindowHint);
     render_window->restoreGeometry(UISettings::values.renderwindow_geometry);
 #if MICROPROFILE_ENABLED
     microProfileDialog->restoreGeometry(UISettings::values.microprofile_geometry);