Fix QFontEngineX11FT compilation

xglyph_format is only available when XRender is present.

Reviewed-by: Fabien Freling
(cherry picked from commit a6642e4659b3d45ffa94f9a3c6413124d49f2b91)

Change-Id: Ibd767c5055c8fb4a7d28ace141f6713f4367d1ba
Reviewed-on: http://codereview.qt.nokia.com/113
Reviewed-by: Paul Olav Tvete <paul.tvete@nokia.com>

src/gui/text/qfontengine_x11.cpp

@@ -1205,7 +1205,9 @@ QFontEngine *QFontEngineX11FT::cloneWithSize(qreal pixelSize) const
         delete fe;
         return 0;
     } else {
+#ifndef QT_NO_XRENDER
         fe->xglyph_format = xglyph_format;
+#endif
         return fe;
     }
 }