implement the null function for the Mips32 subzero compiler

src/IceTargetLowering.cpp

 //===- subzero/src/IceTargetLowering.cpp - Basic lowering implementation --===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the skeleton of the TargetLowering class,
 // specifically invoking the appropriate lowering method for a given
 // instruction kind and driving global register allocation.  It also
 // implements the non-deleted instruction iteration in
 // LoweringContext.
 //
 //===----------------------------------------------------------------------===//
 
 #include "IceAssemblerARM32.h"
+#include "IceAssemblerMIPS32.h"
 #include "IceAssemblerX8632.h"
-#include "assembler_mips32.h"
 #include "IceCfg.h" // setError()
 #include "IceCfgNode.h"
 #include "IceOperand.h"
 #include "IceRegAlloc.h"
 #include "IceTargetLowering.h"
 #include "IceTargetLoweringARM32.h"
 #include "IceTargetLoweringMIPS32.h"
 #include "IceTargetLoweringX8632.h"
 
 namespace Ice {
@@ skipping 409 matching lines @@
     return std::unique_ptr<TargetDataLowering>(TargetData##X::create(Ctx));
 #include "llvm/Config/SZTargets.def"
 
   llvm_unreachable("Unsupported target data lowering");
   return nullptr;
 }
 
 TargetDataLowering::~TargetDataLowering() {}
 
 } // end of namespace Ice