For RHEL package builds we don't regenerate the documentation, but use
the one packaged in the release tarball. Supposedly this is done to
avoid multilib conflicts (where the generated docs might contain
different timestamps per architecture). Maybe this should be revisited
and solved differently, because using the pregenerated docs is
cumbersome.
Anyway, as we use the pregenerated docs, patch them with the latest
fixes.
Related: #1916192
