go.crypto: various: fix appengine compatibility
Fixes golang/go#4102.
R=russross, minux.ma, rsc, agl
CC=golang-dev
https://golang.org/cl/6623053
diff --git a/util.go b/util.go
index 67b287c..daa36d7 100644
--- a/util.go
+++ b/util.go
@@ -2,7 +2,7 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
-// +build linux
+// +build linux,!appengine
// Package terminal provides support functions for dealing with terminals, as
// commonly found on UNIX systems.
