fix doxygen brief in subzero header files

src/IceInstMIPS32.h

 //===- subzero/src/IceInstMIPS32.h - MIPS32 machine instrs --*- C++ -*-===    //
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
-/// This file declares the InstMIPS32 and OperandMIPS32 classes and their
-/// subclasses. This represents the machine instructions and operands used for
-/// MIPS32 code selection.
+/// \brief Declares the InstMIPS32 and OperandMIPS32 classes and their
+/// subclasses.
+///
+/// This represents the machine instructions and operands used for MIPS32 code
+/// selection.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ICEINSTMIPS32_H
 #define SUBZERO_SRC_ICEINSTMIPS32_H
 
 #include "IceDefs.h"
 #include "IceInst.h"
 #include "IceInstMIPS32.def"
 #include "IceOperand.h"
@@ skipping 365 matching lines @@
   void emitMultiDestSingleSource(const Cfg *Func) const;
   void emitSingleDestMultiSource(const Cfg *Func) const;
   void emitSingleDestSingleSource(const Cfg *Func) const;
 
   Variable *DestHi = nullptr;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEINSTMIPS32_H