mme: Fix tests reusing IMSI suffix

Use value 0 to indicate that the test is not really using the generated
imsi, to easily increment it for tests requiring it.

Change-Id: Ia9d70c125b92352f50adfa80a6cb916bfc8acf99
diff --git a/mme/MME_Tests.ttcn b/mme/MME_Tests.ttcn
index 7266496..973c097 100644
--- a/mme/MME_Tests.ttcn
+++ b/mme/MME_Tests.ttcn
@@ -871,7 +871,7 @@
 	var charstring id := testcasename();
 
 	f_init_diameter(id);
-	f_init_s1ap(id, 4);
+	f_init_s1ap(id, 0);
 	f_s1ap_setup(0);
 	f_init_gtp(id);
 
@@ -1112,7 +1112,7 @@
 	var charstring id := testcasename();
 
 	f_init_diameter(id);
-	f_init_s1ap(id, 4);
+	f_init_s1ap(id, 0);
 	f_s1ap_setup(0);
 	f_init_gtp(id);
 
@@ -1126,7 +1126,7 @@
 /* Successful RESET procedure from eNB to MME */
 testcase TC_s1ap_reset() runs on MTC_CT {
 	var charstring id := testcasename();
-	f_init_s1ap(id, 3);
+	f_init_s1ap(id, 0);
 	f_s1ap_setup(0);
 
 	var template (value) S1AP_IEs.Cause reset_cause := {misc := om_intervention};
@@ -1187,7 +1187,7 @@
 	var charstring id := testcasename();
 
 	f_init_diameter(id);
-	f_init_s1ap(id, 4);
+	f_init_s1ap(id, 5);
 	f_s1ap_setup(0);
 
 	var ConnHdlrPars pars := f_init_pars(ue_idx := 0);
@@ -1274,7 +1274,7 @@
 	var charstring id := testcasename();
 
 	f_init_diameter(id);
-	f_init_s1ap(id, 4);
+	f_init_s1ap(id, 6);
 	f_init_gtpv2_s11(id);
 	f_s1ap_setup(0);
 	f_init_gtp(id);