Replace std::iostreams with raw_ostream in TableGen.

- Sorry, I can't help myself.

 - No intended functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74742 91177308-0d34-0410-b5e6-96231b3b80d8

utils/TableGen/InstrEnumEmitter.h

@@ -25,7 +25,7 @@ public:
   InstrEnumEmitter(RecordKeeper &R) : Records(R) {}
 
   // run - Output the instruction set description, returning true on failure.
-  void run(std::ostream &OS);
+  void run(raw_ostream &OS);
 };
 
 } // End llvm namespace