Doxygenize the documentation comments

src/IceTargetLoweringMIPS32.cpp

Index: src/IceTargetLoweringMIPS32.cpp
diff --git a/src/IceTargetLoweringMIPS32.cpp b/src/IceTargetLoweringMIPS32.cpp
index 0adff0394ec87b0ea036a6dcd5b7cf65747a4fed..6c0793f455684162f6de926a9d3c3cbb044bde1e 100644
--- a/src/IceTargetLoweringMIPS32.cpp
+++ b/src/IceTargetLoweringMIPS32.cpp
@@ -6,10 +6,11 @@
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
-//
-// This file implements the TargetLoweringMIPS32 class, which consists almost
-// entirely of the lowering sequence for each high-level instruction.
-//
+///
+/// \file
+/// This file implements the TargetLoweringMIPS32 class, which consists almost
+/// entirely of the lowering sequence for each high-level instruction.
+///
 //===----------------------------------------------------------------------===//
 
 #include "IceTargetLoweringMIPS32.h"