Fix text metrics calculation in Xft support for lwlib

* lwlib/lwlib-Xaw.c (get_text_width_and_height) [HAVE_XFT]:
* lwlib/xlwmenu.c (string_width) [HAVE_XFT]: Use xOff member instead of width.

lwlib/lwlib-Xaw.c

@@ -154,7 +154,7 @@ get_text_width_and_height (Widget widget, char *text,
                           &gi);
       bp = cp ? cp + 1 : NULL;
       h += xft_font->height;
-      if (w < gi.width) w = gi.width;
+      if (w < gi.xOff) w = gi.xOff;
     }
 
   *height = h;

lwlib/xlwmenu.c

@@ -332,7 +332,7 @@ string_width (XlwMenuWidget mw, char *s)
       XftTextExtentsUtf8 (XtDisplay (mw), mw->menu.xft_font,
                           (FcChar8 *) s,
                           strlen (s), &gi);
-      return gi.width;
+      return gi.xOff;
     }
 #endif
 #ifdef HAVE_X_I18N