drm/amdgpu:Add error message when register failed to reach expected value

Add error message when register failed to reach expected value, It will
help discover potential issue.

Signed-off-by: James Zhu <James.Zhu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
1 file changed