drm/etnaviv: avoid cleaning up sched_job when submit succeeded

While the labels may mislead the casual reader, the tail of the function
etnaviv_ioctl_gem_submit is always executed, as a lot of the structures
set up in this function need to be cleaned up regardless of whether the
submit succeeded or failed.

An exception is the newly added drm_sched_job_cleanup, which must only
be called when the submit failed before handing the job to the
scheduler.

Fixes: b827c84f5e84 ("drm/etnaviv: Use scheduler dependency handling")
Reported-by: Michael Walle <[e-mail]>
Signed-off-by: Lucas Stach <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c

···
 		sync_file = sync_file_create(submit->out_fence);
 		if (!sync_file) {
 			ret = -ENOMEM;
-			goto err_submit_job;
+			/*
+			 * When this late error is hit, the submit has already
+			 * been handed over to the scheduler. At this point
+			 * the sched_job must not be cleaned up.
+			 */
+			goto err_submit_put;
 		}
 		fd_install(out_fence_fd, sync_file->file);
 	}
···
 	args->fence = submit->out_fence_id;
 
 err_submit_job:
-	drm_sched_job_cleanup(&submit->sched_job);
+	if (ret)
+		drm_sched_job_cleanup(&submit->sched_job);
 err_submit_put:
 	etnaviv_submit_put(submit);