Fix resource directory processing in PE module

Don't allow descending into a resource directory that is already being processed. Example sample where YARA loops infinitely: [0e87e9a78a81f9180c8fb26183e9fb9785985a5d312cdf4f669c151689336543](https://www.virustotal.com/gui/file/0e87e9a78a81f9180c8fb26183e9fb9785985a5d312cdf4f669c151689336543). YARA-X seems to handle this fine.