[C++11] Remove the R-value reference #if usage from the ADT and Support

libraries. It is now always 1 in LLVM builds.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202580 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Support/FileSystem.h

@@ -664,10 +664,8 @@ private:
 public:
   typedef char char_type;
 
-#if LLVM_HAS_RVALUE_REFERENCES
   mapped_file_region(mapped_file_region&&);
   mapped_file_region &operator =(mapped_file_region&&);
-#endif
 
   /// Construct a mapped_file_region at \a path starting at \a offset of length
   /// \a length and with access \a mode.