Embedding absolute paths might break archive operations for Xcode generator

(Splitting this out of a discussion in !5216 (comment 829543))

In looking through the code in cmGlobalXCodeGenerator::AddDependAndLinkInformation() leading up to the changes in !5216 (merged), I noticed that we seem to be adding directories to the search paths based on the output directory of targets. I think this will be using the wrong paths when carrying out an archive operation. It is embedding the regular build paths, but as we've discussed in earlier work, those paths can change for archiving. The specific parts of the code I'm talking about can be found here, here and here.

We need to come up with a way to confirm whether the above represents a real problem or not.

Cc: @gusc