Fix wrong logic in openSubdiv_setEvaluatorCoarsePositions

Issue was that evaluator.SetCoarsePositions() is expecting number
of floats in the array to be passed, but the C-API function used
to pass number of vertices there.
Remove debug print from adaptive evaluator's initialization

That's not good at all if an application which uses OpenSubdiv
library will suddenly have more console output coming from the
OpenSubdiv library.
Merge pull request #279 from Nazg-Gul/dev

Fix wrong logic in openSubdiv_setEvaluatorCoarsePositions

Nice catch - thanks for submitting it !