crypto: rockchip - fix to check return value

crypto_engine_alloc_init may fail, e.g., as result of a fail of
devm_kzalloc or kthread_create_worker. Other drivers (e.g.,
amlogic-gxl-core.c, aspeed-acry.c, aspeed-hace.c, jr.c, etc.) check
crypto_engine_alloc_init's return value and return -ENOMEM in case
a NULL pointer is returned. This patch inserts a corresponding
return value check to rk3288_crypto.c.

Signed-off-by: Kilian Zinnecker <kilian.zinnecker@mail.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/rockchip/rk3288_crypto.c

@@ -371,6 +371,11 @@ static int rk_crypto_probe(struct platform_device *pdev)
 	}
 
 	crypto_info->engine = crypto_engine_alloc_init(&pdev->dev, true);
+	if (!crypto_info->engine) {
+		err = -ENOMEM;
+		goto err_crypto;
+	}
+
 	crypto_engine_start(crypto_info->engine);
 	init_completion(&crypto_info->complete);