fs: avoid emitting error EBADF for double close

Changed the logic in fs.ReadStream and fs.WriteStream so that
close always calls the prototype method rather than the internal
event listener.

Fixes: https://github.com/nodejs/node/issues/2950
PR-URL: https://github.com/nodejs/node/pull/11225


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>