[CMake] Conditional transitive link libraries

[Stephen Kelly]

Daniel Wirtz wrote:

> Hello all,
> 
> I'm struggling with the CMake "Config"-based package description when
> using two depending packages where the upstream package has optional
> link libraries.

For reference, you have the right answer and the link to the right 
documentation on SO

 http://stackoverflow.com/questions/30568733

Thanks,

Steve.