drm/amd/powerplay: revise clock level setup

Make sure the clock level set only on dpm enabled. Also uvd/vce/soc
clock also changed correspondingly.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>