[CMake] Re: FindSDL.cmake and mingw / msys

[E. Wing]

> And if I check all variables using the "show advanced values",
> SDL_LIBRARY is nowhere. The only other variable is SDL_LIBRARY_TEMP
> showing the value "SDL_LIBRARY_TEMP-NOT-FOUND".
>
> Any clue?

Yeah, this is an artifact of how the script works. The quick answer is
to set the SDL_LIBRARY_TEMP with your SDL library. Once you do that,
SDL_LIBRARY will be generated.

-Eric