On Windows, getargc and getargv reported only the executable path, read
with GetModuleFileNameA in the ANSI code page, and dropped every other
argument. Linux returns the whole command line from /proc/self/cmdline,
and the relinker's Windows entry stub already passes the guest entry all
arguments converted to UTF-8.
Parse GetCommandLineW with CommandLineToArgvW and convert each argument
to UTF-8 with WC_ERR_INVALID_CHARS, as the entry stub does, so getargv
matches the entry's argv and the Linux behaviour. The Linux path is
unchanged.