drm/amdgpu: only set cp active field for kiq queue

The mec ucode will set the CP_HQD_ACTIVE bit while the queue is mapped by
MAP_QUEUES packet. So we only need set cp active field for kiq queue.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>