[3.9] bpo-44174: [Enum] add name-mangling reference (GH-29128)

Author: ethanfurman

Doc/library/enum.rst

@@ -1125,7 +1125,7 @@ and raise an error if the two do not match::
 _Private__names
 """""""""""""""
 
-Private names will be normal attributes in Python 3.11 instead of either an error
+:ref:`Private names <private-name-mangling>` will be normal attributes in Python 3.11 instead of either an error
 or a member (depending on if the name ends with an underscore). Using these names
 in 3.9 and 3.10 will issue a :exc:`DeprecationWarning`.
 
@@ -1152,7 +1152,7 @@ all-uppercase names for members)::
 
 .. note::
 
-   This behavior is deprecated and will be removed in 3.11.
+   This behavior is deprecated and will be removed in 3.12.
 
 .. versionchanged:: 3.5