BSC_Tests: Assign g_pars in TC_assignment_sign

The testcase TC_assignment_sign does not assign g_pars in its
test function. However, it assigns local variable pars but then
never uses it.

- remove local variable pars and assign g_pars instead

Change-Id: Iad65d8ff8bfb98df2b212c69916f1e74dc2c61af
Related: OS#2762
diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index 0dfb708..8380175 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -1558,7 +1558,7 @@
 
 
 private function f_tc_assignment_sign(charstring id) runs on MSC_ConnHdlr {
-	var TestHdlrParams pars := valueof(t_def_TestHdlrPars);
+	g_pars := valueof(t_def_TestHdlrPars);
 	var template PDU_BSSAP exp_compl := tr_BSSMAP_AssignmentComplete(omit, omit);
 	var PDU_BSSAP ass_cmd := valueof(ts_BSSMAP_AssignmentReq(omit, omit));