gbproxy: Test for SGSN-INVOKE-TRACE

Change-Id: I1e46e5c403712eb7972c57e6b6f6eb0850b96ae3
diff --git a/library/BSSGP_Emulation.ttcnpp b/library/BSSGP_Emulation.ttcnpp
index a65dd87..d747ca2 100644
--- a/library/BSSGP_Emulation.ttcnpp
+++ b/library/BSSGP_Emulation.ttcnpp
@@ -301,7 +301,8 @@
 
 private template PDU_BSSGP tr_GLOBAL := (
 	{pDU_BSSGP_SUSPEND:=?}, {pDU_BSSGP_SUSPEND_ACK:=?}, {pDU_BSSGP_SUSPEND_NACK:=?},
-	{pDU_BSSGP_RESUME:=?}, {pDU_BSSGP_RESUME_ACK:=?}, {pDU_BSSGP_RESUME_NACK:=?}
+	{pDU_BSSGP_RESUME:=?}, {pDU_BSSGP_RESUME_ACK:=?}, {pDU_BSSGP_RESUME_NACK:=?},
+	{pDU_BSSGP_SGSN_INVOKE_TRACE:=?}
 );
 
 /* We are in BVC_S_UNBLOCKED state */