isisd: fold up isis_circuit_is_type_set()

see previous commit.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/isisd/isisd.c b/isisd/isisd.c
index df99cd1..9844ae5 100644
--- a/isisd/isisd.c
+++ b/isisd/isisd.c
@@ -1778,7 +1778,7 @@
   if (area->is_type != IS_LEVEL_1_AND_2)
   {
     for (ALL_LIST_ELEMENTS_RO (area->circuit_list, node, circuit))
-      isis_event_circuit_type_change (circuit, is_type);
+      isis_circuit_is_type_set (circuit, is_type);
   }
 
   spftree_area_init (area);