[docs] Doc: remove errors about mixed-type comparisons. (issue 12067)

[ezio.melotti at gmail.com]

http://bugs.python.org/review/12067/diff/6175/Doc/reference/expressions.rst
File Doc/reference/expressions.rst (right):

http://bugs.python.org/review/12067/diff/6175/Doc/reference/expressions.rst#newcode1048
Doc/reference/expressions.rst:1048: specific :meth:`__eq__()` and
:meth:`__ne__()`. With ``<``, ``>``,
These should be :meth:`~object.__eq__` (or whatever creates a link to
the __eq__ documention).  The () shouldn't be included.

http://bugs.python.org/review/12067/