This patch adds the dist_schedule clause to the OpenMP distribute directive.
It depends on D15125 [OPENMP] 'omp distribute' directive basic support.
- please post your diffs exactly as said in http://llvm.org/docs/Phabricator.html, with full context available.
- add a test with ast-printing, serialization/deserialization
Please commit a patch with 'ditribute' directive at first