drm/amdgpu:pass ctx->guilty address to entity init

this way the real interested guilty is connected to entity->guilty
pointer, and we can use entity->pointer later in gpu recovery procedure

Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Chunming Zhou <David1.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>