dealloc memory when exiting vesa mode

c_os/user/demo/VBEdemo.cc

@@ -103,5 +103,5 @@ void VBEdemo::run() {
     drawFonts();
 
     // selbst terminieren
-    scheduler.exit();
+    // scheduler.exit();
 }

c_os/user/demo/VBEdemo.h

@@ -10,8 +10,8 @@
 #ifndef __VBEdemo_include__
 #define __VBEdemo_include__
 
-#include "kernel/threads/Thread.h"
 #include "kernel/Globals.h"
+#include "kernel/threads/Thread.h"
 
 class VBEdemo : public Thread {
 
@@ -28,6 +28,10 @@ public:
         kout << "Initialized VBEdemo" << endl;
     }
 
+    ~VBEdemo() override {
+        vesa.initTextMode();
+    }
+
     // Thread-Startmethode
     void run() override;