When we load non absolute pathed .so's this usually implies that we expect the
system to have them in place already, and hence we should not need to ship them.
Without the absolute path to the library, we are also unable to open and send
said library.  Thus we'll do library shipping only for libraries with absolute
paths.

Reviewers: austin, bgamari, simonmar

Reviewed By: simonmar

Subscribers: simonmar, rwbarton, thomie

Differential Revision: https://phabricator.haskell.org/D3469