The tag is present in Lintian version 2.104.264. That is the most recent version we know about.
The named file is being installed in a legacy location.
Modern Debian systems install this file under
Please move this file to a suitable place under the "merged /usr" scheme. Please consult the provided references as to where that might be.
Refer to https://wiki.debian.org/UsrMerge, https://wiki.debian.org/Teams/Dpkg/MergedUsr, Bug#978636, https://lists.debian.org/debian-devel/2020/11/#00232, https://lists.debian.org/debian-devel/2020/12/#00386, https://lists.debian.org/debian-devel-announce/2019/03/msg00001.html, https://rusty.ozlabs.org/?p=236, https://www.linux-magazine.com/Issues/2019/228/Debian-usr-Merge, https://lwn.net/Articles/773342/, and https://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge/ for details.
This is a classification. There is no issue with your package.