fix doxygen brief in subzero header files

src/IceRegAlloc.h

 //===- subzero/src/IceRegAlloc.h - Linear-scan reg. allocation --*- 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 LinearScan data structure used during linear-scan
-/// register allocation, which holds the various work queues for the linear-scan
-/// algorithm.
+/// \brief Declares the LinearScan data structure used during linear-scan
+/// register allocation.
+///
+/// This holds the various work queues for the linear-scan algorithm.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ICEREGALLOC_H
 #define SUBZERO_SRC_ICEREGALLOC_H
 
 #include "IceDefs.h"
 #include "IceOperand.h"
 #include "IceTypes.h"
 
@@ skipping 103 matching lines @@
   llvm::SmallVector<const llvm::SmallBitVector *, REGS_SIZE> RegAliases;
   bool FindPreference = false;
   bool FindOverlap = false;
 
   const bool Verbose;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEREGALLOC_H