ScopInfo: Some code cleanup

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@205957 91177308-0d34-0410-b5e6-96231b3b80d8
ScopInfo: Scalar accesses are zero dimensional

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@205958 91177308-0d34-0410-b5e6-96231b3b80d8