crypto: crypto4xx - fix an error code

If 'kzalloc' fails, we return 0 which means success.
return -ENOMEM instead as already done a few lines above.

Signed-off-by: Christophe JAILLET <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/amcc/crypto4xx_core.c

···
 	dev_set_drvdata(dev, core_dev);
 	core_dev->ofdev = ofdev;
 	core_dev->dev = kzalloc(sizeof(struct crypto4xx_device), GFP_KERNEL);
+	rc = -ENOMEM;
 	if (!core_dev->dev)
 		goto err_alloc_dev;