update vendor

vendor/github.com/vbatts/go-mtree/lchtimes_unix.go

@@ -1,22 +0,0 @@
-// +build darwin dragonfly freebsd openbsd linux netbsd solaris
-
-package mtree
-
-import (
-	"os"
-	"time"
-
-	"golang.org/x/sys/unix"
-)
-
-func lchtimes(name string, atime time.Time, mtime time.Time) error {
-	utimes := []unix.Timespec{
-		unix.NsecToTimespec(atime.UnixNano()),
-		unix.NsecToTimespec(mtime.UnixNano()),
-	}
-	if e := unix.UtimesNanoAt(unix.AT_FDCWD, name, utimes, unix.AT_SYMLINK_NOFOLLOW); e != nil {
-		return &os.PathError{Op: "chtimes", Path: name, Err: e}
-	}
-	return nil
-
-}