Remove outdated comment in func StdStreams
Remove outdated comment in func StdStreams

The code was switched back to x/sys/windows by
https://github.com/moby/term/pull/9.

Signed-off-by: Tobias Klauser <9249c549618448e4c699e8032ba6c7f0d7fd4b7f@distanz.ch>

moby/term