[clang-tidy] cppcoreguidelines-pro-bounds-pointer-arithmetic: ignore generated pointer arithmetic

Summary:
Inside a range-based for-loop over an array, the compiler
generates pointer arithmetic (end = array + size). Don't flag this.

Reviewers: alexfh, sbenza, bkramer, aaron.ballman

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D14582

llvm-svn: 254182