winex11: Only check for fs register corruption on i386.

dlls/winex11.drv/opengl.c

@@ -310,6 +310,7 @@ static BOOL X11DRV_WineGL_InitOpenglInfo(void)
 
     vis = pglXChooseVisual(gdi_display, screen, attribList);
     if (vis) {
+#ifdef __i386__
         WORD old_fs = wine_get_fs();
         /* Create a GLX Context. Without one we can't query GL information */
         ctx = pglXCreateContext(gdi_display, vis, None, GL_TRUE);
@@ -321,6 +322,9 @@ static BOOL X11DRV_WineGL_InitOpenglInfo(void)
             ERR( "You need to set the \"UseFastTls\" option to \"2\" in your X config file.\n" );
             return FALSE;
         }
+#else
+        ctx = pglXCreateContext(gdi_display, vis, None, GL_TRUE);
+#endif
     }
 
     if (ctx) {