Remove duplicate BSD-2-clause copyright section.

debian/copyright

@@ -102,31 +102,6 @@ Copyright: 1995-2005 Jean-loup Gailly
   1995-2005 Mark Adler
 License: zlib
 
-License: BSD-2-clause
- Copyright 2018 Helmut Grohne <helmut@subdivi.de>
- .
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
- .
- 1. Redistributions of source code must retain the above copyright notice,
- this list of conditions and the following disclaimer.
- .
- 2. Redistributions in binary form must reproduce the above copyright notice,
- this list of conditions and the following disclaimer in the documentation
- and/or other materials provided with the distribution.
- .
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- THE POSSIBILITY OF SUCH DAMAGE.
-
 License: BSD-3-clause
  Copyright (c) 2002 Kitware, Inc., Insight Consortium
  All rights reserved.