ggsn: TC_gy_charging_volume_quota_threshold: Fix Gy Threshold/Quota expectancies

open5gs got the Gy Thresholds fixed recently
(e078b33f0c4d6f34d8991f8ad211dd2d9ea977a0).

AS shown in 3GPP TS 29.244 C.2.1.1 diagram, in Diameter Gy the value
sets the trigger for the "remaining credit", not the "used credit".
"ThresholdPFCP = Quota - ThresholdGy"

The test needs to be adapted since it was wrong too.

Change-Id: Ia283ad4919813241e3c33465ba4be2d2e33f5e54
diff --git a/library/DIAMETER_ts32_299_Templates.ttcn b/library/DIAMETER_ts32_299_Templates.ttcn
index 55402ab..ffbd15f 100644
--- a/library/DIAMETER_ts32_299_Templates.ttcn
+++ b/library/DIAMETER_ts32_299_Templates.ttcn
@@ -107,7 +107,9 @@
 	   template (value) octetstring sess_id,
 	   template (value) DCC_NONE_CC_Request_Type req_type,
 	   template (value) AVP_Unsigned32 req_num,
-	   uint32_t validity_time, uint32_t volume_threhsold)
+	   uint32_t validity_time,
+	   uint32_t volume_quota,
+	   uint32_t volume_threhsold := 0)
 := ts_DIAMETER(flags:='01000000'B, cmd_code:=Credit_Control,
 		app_id:=int2oct(c_DIAMETER_CREDIT_CONTROL_AID, 4), hbh_id:=hbh_id, ete_id:=ete_id,
 	avps := {
@@ -121,7 +123,7 @@
 		ts_AVP_Multiple_Services_Credit_Control({
 			ts_AVP_Validity_Time(validity_time),
 			ts_AVP_Granted_Service_Unit({
-				ts_AVP_CC_Total_Octets(volume_threhsold*100)
+				ts_AVP_CC_Total_Octets(volume_quota)
 				}),
 			ts_AVP_3GPP_VolumeQuotaThreshold(volume_threhsold)
 			})