accel/amdxdna: Fix deadlock between context destroy and job timeout

Hardware context destroy function holds dev_lock while waiting for all jobs
to complete. The timeout job also needs to acquire dev_lock, this leads to
a deadlock.

Fix the issue by temporarily releasing dev_lock before waiting for all
jobs to finish, and reacquiring it afterward.

Fixes: 4fd6ca90fc7f ("accel/amdxdna: Refactor hardware context destroy routine")
Reviewed-by: Maciej Falkowski <[e-mail]>
Signed-off-by: Lizhi Hou <[e-mail]>
Link: https://patch.msgid.link/[e-mail]

drivers/accel/amdxdna/aie2_ctx.c

···
 	xdna = hwctx->client->xdna;
 
 	XDNA_DBG(xdna, "%s sequence number %lld", hwctx->name, hwctx->priv->seq);
-	drm_sched_entity_destroy(&hwctx->priv->entity);
-
 	aie2_hwctx_wait_for_idle(hwctx);
 
 	/* Request fw to destroy hwctx and cancel the rest pending requests */
 	aie2_release_resource(hwctx);
 
+	mutex_unlock(&xdna->dev_lock);
+	drm_sched_entity_destroy(&hwctx->priv->entity);
+
 	/* Wait for all submitted jobs to be completed or canceled */
 	wait_event(hwctx->priv->job_free_wq,
 		   atomic64_read(&hwctx->job_submit_cnt) ==
 		   atomic64_read(&hwctx->job_free_cnt));
+	mutex_lock(&xdna->dev_lock);
 
 	drm_sched_fini(&hwctx->priv->sched);
 	aie2_ctx_syncobj_destroy(hwctx);