[OPENMP] Renamed 'DataRecursiveASTVisitor' to just 'RecursiveASTVisitor' for 'reduction' clause and small reformatting after Alp Toker's review.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@211088 91177308-0d34-0410-b5e6-96231b3b80d8