drm/etnaviv: hook up DRM GPU scheduler

This hooks in the DRM GPU scheduler. No improvement yet, as all the
dependency handling is still done in etnaviv_gem_submit. This just
replaces the actual GPU submit by passing through the scheduler.

Allows to get rid of the retire worker, as this is now driven by the
scheduler.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_gem.h

@@ -101,6 +101,7 @@ struct etnaviv_gem_submit_bo {
  * make it easier to unwind when things go wrong, etc).
  */
 struct etnaviv_gem_submit {
+	struct drm_sched_job sched_job;
 	struct kref refcount;
 	struct etnaviv_gpu *gpu;
 	struct dma_fence *out_fence, *in_fence;