crypto: add outputLength option to crypto.createHash

This change adds an outputLength option to crypto.createHash which
allows users to produce variable-length hash values using XOF hash
functons.

Fixes: https://github.com/nodejs/node/issues/28757
PR-URL: https://github.com/nodejs/node/pull/28805


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>