patch 9.0.0618: calling function for reduce() has too much overhead

Problem:    Calling function for reduce() has too much overhead.
Solution:   Do not create a funccall_T every time.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 3223a02..857f211 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -6740,7 +6740,7 @@
     argv[1] = *get_vim_var_tv(VV_VAL);
     newtv.v_type = VAR_UNKNOWN;
 
-    if (eval_expr_typval(expr, argv, 2, &newtv) == FAIL)
+    if (eval_expr_typval(expr, argv, 2, NULL, &newtv) == FAIL)
 	return FALSE;
 
     found = tv_get_bool_chk(&newtv, &error);