crypto: engine - check if BH is disabled during completion

When doing iperf over ipsec with crypto hardware sun8i-ce, I hit some
spinlock recursion bug.

This is due to completion function called with enabled BH.

Add check a to detect this.

Fixes: 735d37b5 ("crypto: engine - Introduce the block request crypto engine framework")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/crypto_engine.c

@@ -53,6 +53,7 @@ static void crypto_finalize_request(struct crypto_engine *engine,
 				dev_err(engine->dev, "failed to unprepare request\n");
 		}
 	}
+	lockdep_assert_in_softirq();
 	req->complete(req, err);
 
 	kthread_queue_work(engine->kworker, &engine->pump_requests);