hlr: actually register simulated MSC as "MSC" identity to HLR

Change-Id: I3b6dc719318db8aef960f3249c16c20deb5793a7
diff --git a/hlr/HLR_Tests.ttcn b/hlr/HLR_Tests.ttcn
index 753f92e..2bf5e57 100644
--- a/hlr/HLR_Tests.ttcn
+++ b/hlr/HLR_Tests.ttcn
@@ -103,6 +103,7 @@
 
 	ccm_pars := c_IPA_default_ccm_pars;
 	ccm_pars.name := "Osmocom TTCN-3 GSUP Simulator";
+	ccm_pars.ser_nr := "MSC-00-00-00-00-00-00";
 
 	vc_IPA := IPA_Emulation_CT.create(id & "-IPA");
 	log("legacy= ", legacy);