libpci: make traverse callback data more generic
libpci: make traverse callback data more generic

No functional change.

This prepares for componentification by sync'ing all the internal
synthetic code with the components branch, except the actual
componentification.

git-svn-id: 14be032f8f42541b1a281b51ae8ea69814daf20e@5014 4b44e086-7f34-40ce-a3bd-00e031736276

BlueBrain/hwloc,BlueBrain/hwloc,BlueBrain/hwloc,BlueBrain/hwloc