Remove more uses of llvm::sys::Path.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184921 91177308-0d34-0410-b5e6-96231b3b80d8
Remove unused include.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184922 91177308-0d34-0410-b5e6-96231b3b80d8