drm/amdgpu: properly guard DC support in navi code

Need to add appropriate ifdef.

Acked-by: Leo Li <sunpeng.li@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
1 file changed