[Bug 37784] No warning to user that wine-mono will not be installed to a 64 bit wineprefix unless wine64 is explicitly invoked

https://bugs.winehq.org/show_bug.cgi?id=37784

--- Comment #1 from Vincent Povirk  ---
Wine Mono installs in a new prefix regardless of the wine command used to
create it. The source of confusion in that bug is that 'wine uninstaller'
invokes the 32-bit uninstaller.exe, which can't see Wine Mono because it
installed as a 64-bit package. This does not impact Wine's ability to run
32-bit .NET software.

I think we should make uninstaller.exe reinvoke itself as 64-bit if it's run in
a wow64 mode, similar to what winecfg does.