This is needed for Navi1X only. And it may help for display missing
or hang issue seen on some high resolution monitors.

V2: no UCLK DPM enablement for Navi10 A0 secure SKU
Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>