Comment # 1 on bug 91789 from Jani Nikula

Presumed fixed by

commit a9ebb3e46c7ef6112c0da466ef0954673ad36832
Author: Harry Wentland <harry.wentland@amd.com>
Date:   Fri Jan 22 17:07:26 2016 -0500

    drm/dp/mst: Calculate MST PBN with 31.32 fixed point