gtphub_test: add test for Del PDP from GGSN side.

Sponsored-by: On-Waves ehi
diff --git a/openbsc/tests/gtphub/gtphub_test.ok b/openbsc/tests/gtphub/gtphub_test.ok
index 8f66b9d..dbc8a6e 100644
--- a/openbsc/tests/gtphub/gtphub_test.ok
+++ b/openbsc/tests/gtphub/gtphub_test.ok
@@ -1,5 +1,8 @@
 test_echo
-test_one_pdp_ctx
+test_one_pdp_ctx (del from SGSN)
+- __wrap_gtphub_resolve_ggsn_addr():
+  returning GGSN addr from imsi 240010123456789 ni internet: 192.168.43.34 port 2123
+test_one_pdp_ctx (del from GGSN)
 - __wrap_gtphub_resolve_ggsn_addr():
   returning GGSN addr from imsi 240010123456789 ni internet: 192.168.43.34 port 2123
 test_user_data