benchmark: fix bench-mkdirp to use recursive option

The original PR didn't update the benchmark after renaming the option.

PR-URL: #23699
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

benchmark/fs/bench-mkdirp.js

@@ -16,7 +16,7 @@ function main({ n }) {
     if (cntr-- <= 0)
       return bench.end(n);
     const pathname = `${tmpdir.path}/${++dirc}/${++dirc}/${++dirc}/${++dirc}`;
-    fs.mkdir(pathname, { createParents: true }, (err) => {
+    fs.mkdir(pathname, { recursive: true }, (err) => {
       r(cntr);
     });
   }(n));