Gb: avoid warnings about not-running timers

If we have  T.timeout  clause in an alt/altstep, we should put
[T.running] as guard expression to avoid warnings about matching
on timers never started - at least for timers where this is a valid
situation.

Change-Id: I96db5c288e0b9c47539cccab8ae7a886d0b9fff3
diff --git a/library/NS_Emulation.ttcn b/library/NS_Emulation.ttcn
index 5924bbe..27acae2 100644
--- a/library/NS_Emulation.ttcn
+++ b/library/NS_Emulation.ttcn
@@ -142,13 +142,13 @@
 		var ASP_Event evt;
 
 		/* transition to DEAD if t_alive times out */
-		[] Tns_alive.timeout {
+		[Tns_alive.running] Tns_alive.timeout {
 			log("Tns-alive expired: changing to DEAD_BLOCKED + starting Tns-test");
 			f_change_state(NSE_S_DEAD_BLOCKED);
 			Tns_test.start;
 		}
 
-		[] Tns_test.timeout {
+		[Tns_test.running] Tns_test.timeout {
 			log("Tns-test expired: sending NS-ALIVE");
 			f_sendAlive();
 		}