Make some DataLayout pointers const.

No functionality change. Just reduces the noise of an upcoming patch.

llvm-svn: 202087
diff --git a/llvm/lib/Transforms/InstCombine/InstCombine.h b/llvm/lib/Transforms/InstCombine/InstCombine.h
index 241db7a..2a4b8a1 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombine.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombine.h
@@ -81,7 +81,7 @@
 class LLVM_LIBRARY_VISIBILITY InstCombiner
                              : public FunctionPass,
                                public InstVisitor<InstCombiner, Instruction*> {
-  DataLayout *DL;
+  const DataLayout *DL;
   TargetLibraryInfo *TLI;
   bool MadeIRChange;
   LibCallSimplifier *Simplifier;
@@ -108,7 +108,7 @@
 
   virtual void getAnalysisUsage(AnalysisUsage &AU) const;
 
-  DataLayout *getDataLayout() const { return DL; }
+  const DataLayout *getDataLayout() const { return DL; }
 
   TargetLibraryInfo *getTargetLibraryInfo() const { return TLI; }