Issue #21875: Remove vestigial references to Classic Mac OS in os module docs.

Doc/library/os.rst

@@ -53,7 +53,7 @@ Notes on the availability of these functions:
 .. data:: name
 
    The name of the operating system dependent module imported.  The following
-   names have currently been registered: ``'posix'``, ``'nt'``, ``'mac'``,
+   names have currently been registered: ``'posix'``, ``'nt'``,
    ``'ce'``, ``'java'``.
 
    .. seealso::
@@ -1891,12 +1891,6 @@ features:
    * :attr:`st_gen` - file generation number
    * :attr:`st_birthtime` - time of file creation
 
-   On Mac OS systems, the following attributes may also be available:
-
-   * :attr:`st_rsize`
-   * :attr:`st_creator`
-   * :attr:`st_type`
-
    .. note::
 
       The exact meaning and resolution of the :attr:`st_atime`,

Lib/os.py

-r"""OS routines for Mac, NT, or Posix depending on what system we're on.
+r"""OS routines for NT or Posix depending on what system we're on.
 
 This exports:
   - all functions from posix, nt or ce, e.g. unlink, stat, etc.