docs: Fix a build error in coding-style.rst

A reference typo caused an unsightly build error; fix it.
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

Documentation/translations/zh_CN/process/coding-style.rst

 .. include:: ../disclaimer-zh_CN.rst
 
-:Original: :ref:`Documentation/process/coding-style.rst <codingsytle>`
+:Original: :ref:`Documentation/process/coding-style.rst <codingstyle>`
 
 .. _cn_codingstyle: