gtphub: fix ares segfault: add missing initialization.
The struct gtphub_resolved_ggsn was not initialized properly, so that adding
it to a list caused a segmentation fault.
diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c
index e86620f..95bf7f7 100644
--- a/openbsc/src/gprs/gtphub.c
+++ b/openbsc/src/gprs/gtphub.c
@@ -1704,6 +1704,8 @@
ggsn = talloc_zero(osmo_gtphub_ctx, struct gtphub_resolved_ggsn);
OSMO_ASSERT(ggsn);
+ INIT_LLIST_HEAD(&ggsn->entry);
+ expiring_item_init(&ggsn->expiry_entry);
ggsn->peer = pp;
gtphub_port_ref_count_inc(pp);