drm/lima: use scheduler dependency tracking

Nothing special going on here.

Aside reviewing the code, it seems like drm_sched_job_arm() should be
moved into lima_sched_context_queue_task and put under some mutex
together with drm_sched_push_job(). See the kerneldoc for
drm_sched_push_job().

v2: Rebase over renamed functions to add dependencies.

Reviewed-by: Qiang Yu <yuq825@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Qiang Yu <yuq825@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: lima@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210805104705.862416-9-daniel.vetter@ffwll.ch

drivers/gpu/drm/lima/lima_sched.h

@@ -23,9 +23,6 @@ struct lima_sched_task {
 	struct lima_vm *vm;
 	void *frame;
 
-	struct xarray deps;
-	unsigned long last_dep;
-
 	struct lima_bo **bos;
 	int num_bos;