drm/amdgpu/virtual_dce: add case for topaz for disable_dce

This asic has no DCE block.  Also clarify the error message
for unmatched chips.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Alex Deucher 2016-08-08 14:40:04 -04:00
commit 2579de4394