ggsn/pgw: Fix Gy CCR Reporting-Reason expectancies

The Reporting-Reason can be in different places depending on its values.
In the case of TERMINATION, we expect it to be FINAL so we know its
location.

Change-Id: Id33b9bb2f7b469e03a0761dc8807770cfdf77fcc
diff --git a/pgw/PGW_Tests.ttcn b/pgw/PGW_Tests.ttcn
index d8ee60d..e1f49ab 100644
--- a/pgw/PGW_Tests.ttcn
+++ b/pgw/PGW_Tests.ttcn
@@ -409,7 +409,7 @@
 					tr_AVP_Multiple_Services_Credit_Control(content := superset(
 						tr_AVP_Requested_Service_Unit,
 						tr_AVP_Used_Service_Unit,
-						tr_AVP_3GPP_Reporting_Reason,
+						/* tr_AVP_3GPP_Reporting_Reason, can be sometimes inside UsedServiceUnit */
 						tr_AVP_3GPP_QoS_Information,
 						tr_AVP_GI_3GPP_RatType(rat_type)
 					)),
@@ -459,6 +459,7 @@
 					tr_AVP_Multiple_Services_Credit_Control(content := superset(
 						/* tr_AVP_Requested_Service_Unit, Only in INIT and UPDATE */
 						tr_AVP_Used_Service_Unit,
+						tr_AVP_3GPP_Reporting_Reason(FINAL),
 						tr_AVP_3GPP_QoS_Information,
 						tr_AVP_GI_3GPP_RatType(rat_type)
 					)),