drm/amd/display: Notify powerplay the min_dcef clock

powerplay can notify smu to recalculates the maximum deep-sleep
divider display allowed.

Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>