when uvd is idle, we gate uvd clock.
and uvd is busy, we ungate uvd clock.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>