Refer to specific version of license LGPL-2+.

Changes-By: lintian-brush
Fixes: lintian: copyright-refers-to-symlink-license
See-also: https://lintian.debian.org/tags/copyright-refers-to-symlink-license.html
Fixes: lintian: copyright-refers-to-versionless-license-file
See-also: https://lintian.debian.org/tags/copyright-refers-to-versionless-license-file.html

debian/copyright

@@ -67,4 +67,4 @@ License: LGPL-2+
  02110-1301, USA
  .
  On Debian systems, the complete text of the GNU Lesser General
- Public License can be found in `/usr/share/common-licenses/LGPL'.
+ Public License can be found in `/usr/share/common-licenses/LGPL-2'.