The tag is present in Lintian version 2.104.328. That is the most recent version we know about.
This symlink contains two successive slashes (//). This is in violation of policy, where it is stated that symlinks should be as short as possible
If you use debhelper, running dh_link after creating the package structure will fix this problem for you.
Please refer to Debian Policy Manual section 10.5 for details.