bpo-30125: Fix faulthandler.disable() on Windows (#1240)

* bpo-30125: Cleanup faulthandler.c

* Use size_t type for iterators
* Add { ... }

* bpo-30125: Fix faulthandler.disable() on Windows

On Windows, faulthandler.disable() now removes the exception handler
installed by faulthandler.enable().
2 files changed