let games gracefully exit

src/yuzu/bootmanager.h

@@ -11,6 +11,7 @@
 #include <QImage>
 #include <QStringList>
 #include <QThread>
+#include <QTimer>
 #include <QTouchEvent>
 #include <QWidget>
 
@@ -87,6 +88,15 @@ public:
      * Requests for the emulation thread to stop running
      */
     void RequestStop() {
+        QTimer::singleShot(5000, this, &EmuThread::ForceStop);
+    }
+
+private slots:
+    void ForceStop() {
+        if (!IsRunning()) {
+            return;
+        }
+        LOG_WARNING(Frontend, "Force stopping EmuThread");
         stop_source.request_stop();
         SetRunning(false);
     }