Rewrite a cold use of std::sort to array_pod_sort.

No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191173 91177308-0d34-0410-b5e6-96231b3b80d8
array_pod_sort loses some type safety, better use the right types.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@191174 91177308-0d34-0410-b5e6-96231b3b80d8