commit a17d4996 upstream.

Just keep it working, seems to fix some PLL problems.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=73378Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>