Temporary disable formatting error

This should silence the buildbots until we understand if the clang-format
changes in r221125 have been intentional. See reply on cfe-commits for details.

git-svn-id: https://llvm.org/svn/llvm-project/polly/trunk@221159 91177308-0d34-0410-b5e6-96231b3b80d8