Update golang.org/x/sys

Update our vendored copy of golang.org/x/sys to version
9aade4d3a3b7e6d876cd3823ad20ec45fc035402 to get the new Major() and
Minor() helpers.

Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>

vendor/golang.org/x/sys/unix/file_unix.go

@@ -0,0 +1,27 @@
+// Copyright 2017 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.
+
+package unix
+
+import (
+	"os"
+	"syscall"
+)
+
+// FIXME: unexported function from os
+// syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
+func syscallMode(i os.FileMode) (o uint32) {
+	o |= uint32(i.Perm())
+	if i&os.ModeSetuid != 0 {
+		o |= syscall.S_ISUID
+	}
+	if i&os.ModeSetgid != 0 {
+		o |= syscall.S_ISGID
+	}
+	if i&os.ModeSticky != 0 {
+		o |= syscall.S_ISVTX
+	}
+	// No mapping for Go's ModeTemporary (plan9 only).
+	return
+}