evas: Evas_Gl_X11 - add missing eng_window_free

Summary:
add missing eng_window_free before return from eng_setup.
@fix

Test Plan: N/A

Reviewers: cedric, raster, devilhorns, stefan_schmidt

Subscribers: cedric

Differential Revision: https://phab.enlightenment.org/D1345

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>

src/modules/evas/engines/gl_x11/evas_engine.c

@@ -1022,6 +1022,7 @@ eng_setup(Evas *eo_e, void *in)
                                                 &evgl_funcs,
                                                 e->output.w, e->output.h))
           {
+             eng_window_free(ob);
              free(re);
              return 0;
           }