src: perf_hooks: fix wrong sized delete

Depending on the allocator, existing code leaks memory.

PR-URL: https://github.com/nodejs/node/pull/16898


Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Khaidi Chu <i@2333.moe>