Delete LLVM_DELETED_FUNCTION from coding standards

It didn't seem worth leaving behind a guideline to use '= delete' to
make a class uncopyable. That's a well known C++ design pattern.

Reported on the mailing list and in PR22724.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230776 91177308-0d34-0410-b5e6-96231b3b80d8

docs/CodingStandards.rst

@@ -1301,34 +1301,6 @@ that the enum expression may take any representable value, not just those of
 individual enumerators. To suppress this warning, use ``llvm_unreachable`` after
 the switch.
 
-Use ``LLVM_DELETED_FUNCTION`` to mark uncallable methods
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-Prior to C++11, a common pattern to make a class uncopyable was to declare an
-unimplemented copy constructor and copy assignment operator and make them
-private. This would give a compiler error for accessing a private method or a
-linker error because it wasn't implemented.
-
-With C++11, we can mark methods that won't be implemented with ``= delete``.
-This will trigger a much better error message and tell the compiler that the
-method will never be implemented. This enables other checks like
-``-Wunused-private-field`` to run correctly on classes that contain these
-methods.
-
-For compatibility with MSVC, ``LLVM_DELETED_FUNCTION`` should be used which
-will expand to ``= delete`` on compilers that support it. These methods should
-still be declared private. Example of the uncopyable pattern:
-
-.. code-block:: c++
-
-  class DontCopy {
-  private:
-    DontCopy(const DontCopy&) LLVM_DELETED_FUNCTION;
-    DontCopy &operator =(const DontCopy&) LLVM_DELETED_FUNCTION;
-  public:
-    ...
-  };
-
 Don't evaluate ``end()`` every time through a loop
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^