The tag is present in Lintian version 2.104.234. That is the most recent version we know about.
The package installs the listed file to a directory in / (the filesystem root) rather than to the corresponding directory inside /usr.
Debian requires systems to mount /usr prior to invoking init (using an initramfs if necessary) so any executables, libraries, or other files placed in / for use by early portions of the system init no longer need to do so.
Moving a file from / to /usr (especially an executable in /bin or /sbin) will often require a compatibility symlink to the new location, as other software may invoke it by absolute path.
A compatibility symlink to the corresponding file in /usr will not trigger this warning but a symlink to anywhere else will.
This is a classification. There is no issue with your package.