Comment # 7 on bug 110671 from Tomas Bzatek

The offending commit is

commit 5fc0cbfad4564856ee0f323d3f88a7cff19cc3f1
Author: Wenjing Liu <Wenjing.Liu@amd.com>
Date:   Fri Jan 18 18:19:51 2019 -0500

    drm/amd/display: determine if a pipe is synced by plane state