Remove useless variables 'swfStage' and 'stage'

'swfStage' gets set to 'stage' in updategraphicsmode() but... that does
absolutely nothing, because they both contain exactly the same thing.
And these variables aren't referenced anywhere else. So I'm removing
both of these variables.

desktop_version/src/titlerender.cpp

@@ -12,8 +12,6 @@
 
 extern scriptclass script;
 
-Stage stage;
-Stage swfStage;
 int temp;
 
 int tr;
@@ -24,7 +22,6 @@ std::string tempstring;
 
 void updategraphicsmode()
 {
-    swfStage = stage;
 }
 
 void titlerender()

desktop_version/src/titlerender.h

@@ -14,8 +14,6 @@ public:
     int frameRate;
 };
 
-extern Stage stage;
-extern Stage swfStage;
 extern int temp;
 
 void titlerender();