drm/amdgpu: use mode-2 reset for RAS poison consumption

Switch from mode-1 reset to mode-2 for poison consumption.

Signed-off-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Stanley.Yang <Stanley.Yang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>