Get rid of the direct access abuse of FullFramePixelBuffer's data
diff --git a/common/rfb/VNCServerST.h b/common/rfb/VNCServerST.h
index 88d0255..ed7833a 100644
--- a/common/rfb/VNCServerST.h
+++ b/common/rfb/VNCServerST.h
@@ -92,7 +92,7 @@
     virtual void add_changed(const Region &region);
     virtual void add_copied(const Region &dest, const Point &delta);
     virtual void setCursor(int width, int height, const Point& hotspot,
-                           void* cursorData, void* mask);
+                           const void* cursorData, const void* mask);
     virtual void setCursorPos(const Point& p);
 
     virtual void bell();