linux-next: build warning after merge of the jc_docs tree

Hi all,

After merging the jc_docs tree, today's linux-next build (htmldocs)
produced this warning:

Documentation/translations/zh_CN/mips/index.rst:5: WARNING: undefined label: index (if the link has no caption the label must precede a section header)

Introduced by commit

  b8e724fd7117 ("doc/zh_CN: add mips index.rst translation")

-- 
Cheers,
Stephen Rothwell