Bug#931415: sdl2-client crashes when entering game

[Marko Lindqvist]

Package: freeciv
Version: 2.6.0-2

 Some people are reporting to us in freeciv upstream that sdl2-client
always crashes for them when entering the game. We have a fix for that
as 0001-Fix-arithmetic-error-in-SDL2-create_line.patch (2019-07-03
02:18 AM) in http://www.hostedredmine.com/issues/824589 You may want
to backport that fix.

 - ML