py: Eliminate some cases which trigger unused parameter warnings.
diff --git a/py/objenumerate.c b/py/objenumerate.c
index 36f7208..9cdd4fd 100644
--- a/py/objenumerate.c
+++ b/py/objenumerate.c
@@ -57,6 +57,7 @@
     o->iter = mp_getiter(vals[0].u_obj);
     o->cur = vals[1].u_int;
 #else
+    (void)n_kw;
     mp_obj_enumerate_t *o = m_new_obj(mp_obj_enumerate_t);
     o->base.type = type_in;
     o->iter = mp_getiter(args[0]);