fix doxygen brief in subzero header files

src/IceTypeConverter.cpp

 //===- subzero/src/IceTypeConverter.cpp - Convert ICE/LLVM Types ----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
-/// This file implements how to convert LLVM types to ICE types, and ICE types
-/// to LLVM types.
+/// \brief Implements how to convert LLVM types to ICE types, and ICE types to
+/// LLVM types.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "IceTypeConverter.h"
 
 #include "llvm/Support/raw_ostream.h"
 
 namespace Ice {
 
 TypeConverter::TypeConverter(llvm::LLVMContext &Context) {
@@ skipping 28 matching lines @@
   switch (LLVMTy->getTypeID()) {
   case llvm::Type::PointerTyID:
   case llvm::Type::FunctionTyID:
     return getPointerType();
   default:
     return Ice::IceType_NUM;
   }
 }
 
 } // end of Ice namespace.