Blender Git Loki

OpenSubdiv: Cleanup, remove unused topology orientation code

The code was trying to make winding consistent and manifold, same as
OpenSubdiv expects it to.

Unfortunately, the code was having some issues in corner cases so the
winding wasn't really correct.
Fortunately, the latter (compared to when this code was originally
written) supports orientation on OpenSubdiv side.

Removing code which is currently unused in Blender and which had
known issues. Is simple enough to bring the code from Git history
if the functionality is needed in the future.