xserver-xorg-video-amdgpu: Changes to 'ubuntu'

[Timo Aaltonen]

New branch 'ubuntu' available with the following commits:
commit 95fccd07766b6c6e7bdcd1e1f2b0432be8a36ab8
Author: Timo Aaltonen <tjaal...@debian.org>
Date:   Wed Aug 19 15:39:56 2015 +0300

    update the changelog for ubuntu