Update the call to llvm::sys::fs::UniqueID to match the definition:...

Update the call to llvm::sys::fs::UniqueID to match the definition: UniqueID(uint64_t Device, uint64_t File)
Fixes CID 1095247




git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@215896 91177308-0d34-0410-b5e6-96231b3b80d8