Issue #9642: Fix filesystem encoding initialization: use the ANSI code page on Windows if the mbcs codec is not available, and fail with a fatal error if we cannot get the locale encoding (if nl_langinfo(CODESET) is not available) instead of using UTF-8.

#include "Python.h"

#ifndef PLATFORM
#define PLATFORM "unknown"
#endif

const char *
Py_GetPlatform(void)
{
	return PLATFORM;
}