[CMake] Path to installed target

[Alexey Livshits]

As I mentioned above, there are targets foo1 and foo2, build from foo
sources, and the output name has to be foo. This is the conflict. The
test depends from foo1 and bar2.

> If you don't explain the problem more clearly, people won't be able to
> help you; particularly because I suspect that you are asking the wrong
> question...

Well, my question was very clear imho, I just wanted to know, how to
determine the path. In fact I'm looking for a better approach how to
organize my project, but this is not the point here.

-- 
BG,
Alexey