[mythtv] Ticket #4270: MythTV on Windows (with MinGW)

[Andrei Tanas]

> Given that there is now a MediaMonitorWindows that I assume works,
> can we remove all the #ifndef _WIN32 guards from these:
> 
> programs/mythfrontend/main.cpp
yes

> mythgallery/mythgallery/iconview.cpp
yes

> mythmusic/mythmusic/cdrip.cpp
Cdrip needs cdda libs and is currently excluded from MinGW configuration.

I will test if this stuff actually works on Windows and submit a patch.