bsc: Fix IPA_CFG_PORT handling several connections

Recent commit changing the layout of bts/trx port config made
IPA_CFG_PORT be connected severa times when calling f_ipa_rsl_start()
for each BTS/TRX.

Let's have separate ports per BTS/TRX as done in other ports in the
test_CT component.

This avoid this error when calling f_ipa_rsl_stop():
"""
Dynamic test case error: Port IPA_CFG_PORT has more than one active
connections. Message can be sent on it only with explicit addressing.
"""

Change-Id: I916186c87c398ebb2d7f82f73b94de75034e346d
diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index b445709..8a7d465 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -612,8 +612,8 @@
 	port IPA_CODEC_PT IPA; /* Required for compilation of TC_rsl_unknown_unit_id() */
 	/* CTRL muxed over IPA in SCCPlite conn BSC<->MSC (or BSC-NAT) */
 	port IPA_CTRL_PT SCCPLITE_IPA_CTRL;
-	/* Configure/manage IPA_Emulation: */
-	port IPA_CFG_PT IPA_CFG_PORT;
+	/* Configure/manage IPA_Emulation per-BTS/TRX port: */
+	port IPA_CFG_PT IPA_CFG_PORT[NUM_BTS][NUM_TRX];
 
 	var MGCP_Emulation_CT vc_MGCP;
 	port TELNETasp_PT BSCVTY;
@@ -953,7 +953,7 @@
 	}
 
 	map(clnt.vc_IPA:IPA_PORT, system:IPA_CODEC_PT);
-	connect(clnt.vc_IPA:CFG_PORT, self:IPA_CFG_PORT);
+	connect(clnt.vc_IPA:CFG_PORT, self:IPA_CFG_PORT[idx.bts][idx.trx]);
 	if (handler_mode) {
 		connect(clnt.vc_IPA:IPA_RSL_PORT, clnt.vc_RSL:IPA_PT);
 	} else {
@@ -982,7 +982,7 @@
 	}
 }
 
-function f_ipa_rsl_stop(inout IPA_Client clnt) runs on test_CT {
+function f_ipa_rsl_stop(inout IPA_Client clnt, BtsTrxIdx idx := {0, 0}) runs on test_CT {
 	var IPL4asp_Types.Result res := {
 		errorCode := omit,
 		connId := omit,
@@ -997,7 +997,7 @@
 	/* Alive components don't finish sockets (TCP FIN) when they are
 	 * stopped. Hence, we need to manually call close() on them to make sure
 	 * the IUT knows about it. */
-	f_ipa_cfg_disconnect(IPA_CFG_PORT, res);
+	f_ipa_cfg_disconnect(IPA_CFG_PORT[idx.bts][idx.trx], res);
 
 	clnt.vc_IPA.stop;
 	if (isbound(clnt.vc_RSL)) {