Redirect DataLayout from TargetMachine to Module in MachineFunction

Summary:
This change is part of a series of commits dedicated to have a
single DataLayout during compilation by using always the one owned by the
module.

Reviewers: echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10984

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241610 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MachineFunction.h

@@ -155,6 +155,9 @@ public:
   MachineModuleInfo &getMMI() const { return MMI; }
   MCContext &getContext() const { return Ctx; }
 
+  /// Return the DataLayout attached to the Module associated to this MF.
+  const DataLayout &getDataLayout() const;
+
   /// getFunction - Return the LLVM function that this machine code represents
   ///
   const Function *getFunction() const { return Fn; }