Merge tag 'docs-5.2-fixes2' of git://git.lwn.net/linux

Pull documentation fixes from Jonathan Corbet:
 "The Sphinx 2.0 release contained a few incompatible API changes that
  broke our extensions and, thus, the documentation build in general.
  Who knew that those deprecation warnings it was outputting actually
  meant we should change something? This set of fixes makes the build
  work again with Sphinx 2.0 and eliminates the warnings for 1.8. As
  part of that, we also need a few fixes to the docs for places where
  the new Sphinx is more strict.

  It is a bit late in the cycle for this kind of change, but it does fix
  problems that people are experiencing now.

  There has been some talk of raising the minimum version of Sphinx we
  support. I don't want to do that abruptly, though, so these changes
  add some glue to continue to support versions back to 1.3. We will be
  adding some infrastructure soon to nudge users of old versions
  forward, with the idea of maybe increasing our minimum version (a...