docs: add Documentation/.renames.txt

This is the result of running:

  scripts/documentation-gen-renames.py --rev v6.17-rc3 > Documentation/.renames.txt

This file records renames in the Documentation/ directory so that we
can use it to quickly generate HTML redirects from removed paths.

Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250905144608.577449-3-vegard.nossum@oracle.com>