Trivial change llvm::CreateInfoOutputFile() to return raw_ostream. NFC

This is NFC w.r.t upstream but allows us to return raw_null_ostream in our
downstream fork without changing the interface.

Author: dsandersllvm

llvm/include/llvm/ADT/Statistic.h

@@ -177,8 +177,8 @@ void EnableStatistics(bool DoPrintOnExit = true);
 /// Check if statistics are enabled.
 bool AreStatisticsEnabled();
 
-/// Return a file stream to print our output on.
-std::unique_ptr<raw_fd_ostream> CreateInfoOutputFile();
+/// Return a stream to print our output on.
+std::unique_ptr<raw_ostream> CreateInfoOutputFile();
 
 /// Print statistics to the file returned by CreateInfoOutputFile().
 void PrintStatistics();

llvm/lib/Support/Timer.cpp

@@ -93,7 +93,7 @@ void llvm::initTimerOptions() {
   *SortTimers;
 }
 
-std::unique_ptr<raw_fd_ostream> llvm::CreateInfoOutputFile() {
+std::unique_ptr<raw_ostream> llvm::CreateInfoOutputFile() {
   const std::string &OutputFilename = getLibSupportInfoOutputFilename();
   if (OutputFilename.empty())
     return std::make_unique<raw_fd_ostream>(2, false); // stderr.