Complete the driver `reload` and `dump` functionality for WIN32 builds

[jimklimov]

With #1903 the driver shared main.c and upsdrvctl program were extended with support for live reload of configuration ported from precedents in upsd and upsmon. For simplicity the first efforts (PRs #1906, #1912) dealt with POSIX platforms, leaving placeholders and "FIXME" comments for the Windows branch of code. Original logic in upsd and upsmon did offer Windows support for these abilities - so this issue is a reminder to complete the port to handle that platform too.

[jimklimov]

Note: reload-or-error (via socket protocol for all platforms) is now completed and tested for both drivers and upsdrvctl in PR #1922