gtphub_test: add some cleanup asserts.

Sponsored-by: On-Waves ehi
diff --git a/openbsc/tests/gtphub/gtphub_test.c b/openbsc/tests/gtphub/gtphub_test.c
index fea55e0..f5f2c88 100644
--- a/openbsc/tests/gtphub/gtphub_test.c
+++ b/openbsc/tests/gtphub/gtphub_test.c
@@ -625,6 +625,11 @@
 	LVL2_ASSERT(llist_empty(&hub->to_gsns[GTPH_SIDE_GGSN][plane_idx].peers));
 	LVL2_ASSERT(llist_empty(&hub->to_gsns[GTPH_SIDE_SGSN][plane_idx].peers));
 
+	LVL2_ASSERT(llist_empty(&hub->tunnels));
+	LVL2_ASSERT(llist_empty(&hub->pending_deletes));
+	LVL2_ASSERT(llist_empty(&hub->ggsn_lookups));
+	LVL2_ASSERT(llist_empty(&hub->resolved_ggsns));
+
 	gtphub_free(hub);
 	return 1;
 }