removed extra = in assignment

kern/synchprobs/traffic_synch.c

@@ -109,7 +109,7 @@ static void clearint(car * done)
     // if this is the only element
     if (temp == active->back)
     {
-      active->back == NULL;
+      active->back = NULL;
     }
     
     active->front = active->front->next;