Check the handle for font package before remove it.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@4667 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/Console/GraphicsConsoleDxe/GraphicsConsole.c

@@ -618,12 +618,10 @@ GraphicsConsoleControllerDriverStop (
     //
     // Remove the font pack
     //
-#if 1
+    if (Private->HiiHandle != NULL) {
-    HiiLibRemovePackages (Private->HiiHandle);
+      HiiLibRemovePackages (Private->HiiHandle);
-    mFirstAccessFlag = TRUE;
+      mFirstAccessFlag = TRUE;
-#else    
+    }
-    mHii->RemovePack (mHii, Private->HiiHandle);
-#endif
 
     //
     // Free our instance data