Update vendors.

Signed-off-by: Lantao Liu <lantaol@google.com>

vendor/github.com/fsnotify/fsnotify/open_mode_bsd.go

@@ -0,0 +1,11 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build freebsd openbsd netbsd dragonfly
+
+package fsnotify
+
+import "golang.org/x/sys/unix"
+
+const openMode = unix.O_NONBLOCK | unix.O_RDONLY