NS_Emulation: Use the "endpoint" mode of NS_Provider_IPL4

Thew newly-introduced "endpoint" mode of NS_Provider_IPL4 allows us
to have multiple NS-VC within one endpoint.  NS_CT takes care of
creating the NS_Provider_IPL4 components on-the-fly, and then
associating the per-NSVC components with it.

For the user nothing changes, other than that he can now configure
multiple NSVCs with identical local IP + port, which was not possible
before.

Change-Id: Id7360f17e528706e8145d33a14550789d50cded9
diff --git a/library/NS_Provider_IPL4.ttcn b/library/NS_Provider_IPL4.ttcn
index 33f3529..8145c13 100644
--- a/library/NS_Provider_IPL4.ttcn
+++ b/library/NS_Provider_IPL4.ttcn
@@ -195,4 +195,11 @@
 
 } /* main */
 
+function f_nspip_add_nsvc(NS_Provider_IPL4_CT vc_ipep, charstring remote_ip, PortNumber remote_port, NSVC_CT vc_nsvc)
+runs on NS_CT {
+	NSPIP_PROC.call(NSPIP_add_nsvc:{remote_ip, remote_port, vc_nsvc}) to vc_ipep {
+		[] NSPIP_PROC.getreply(NSPIP_add_nsvc:{?,?,?});
+	}
+}
+
 } /* module */