src: rename PROVIDER_FSREQWRAP to PROVIDER_FSREQCALLBACK

PR-URL: https://github.com/nodejs/node/pull/21971


Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>