dummy vout: check for sys->pool before deleting it.

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

modules/misc/dummy/vout.c

@@ -91,7 +91,8 @@ void CloseVideo(vlc_object_t *object)
     vout_display_t *vd = (vout_display_t *)object;
     vout_display_sys_t *sys = vd->sys;
 
-    picture_pool_Delete(sys->pool);
+    if (sys->pool)
+        picture_pool_Delete(sys->pool);
     free(sys);
 }