xserver-xorg-driver-ati must be configured in order for Launchpad to forward bugs to the project's developers.
Bugs are tracked in freedesktop.org Bugzilla.
Getting started with bug tracking in Launchpad.Ubuntu also tracks bugs for packages derived from this project: xserver-xorg-driver-ati in Ubuntu, xserver-xorg-video-ati in Ubuntu, xserver-xorg-video-ati-hwe-16.04 in Ubuntu.