fs: runtime deprecation for fs.SyncWriteStream

This API was never intended to be made public and was docs-only
deprecated in Node.js 6.x. This upgrades to a runtime deprecation
for Node.js 8.0.0

PR-URL: https://github.com/nodejs/node/pull/10467


Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>