[mythtv] MingW commits broke OS X builds

[Andrei Tanas]

> On Dec 11, 2007 7:11 PM, Nigel Pearson <nigel at ind.tansu.com.au> wrote:
> > I'm still suffering circular library dependencies
> That is a hard one, but I am working on it.
> 
> Ooo, that's good to hear.  That was one of the stumbling blocks I ran
> into when I was working on a Cygwin/MinGW port last year.
> 
> Andrei, how did you get around that in your port?

http://svn.mythtv.org/trac/ticket/4270#comment:22

I created .def files with symbols that needed to be imported (there's
relatively few in one direction), which are used to make "export libraries"
before linking.