drm/amdgpu: refine ras error kernel log print

refine ras error kernel log to avoid user-ridden ambiguity.

Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>