crypto: atmel-sha204a - Use device-managed registration API

Use devm_hwrng_register to get rid of manual
unregistration.

Signed-off-by: Chuhong Yuan <[e-mail]>
Acked-by: Ludovic Desroches <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/atmel-sha204a.c

···
 	i2c_priv->hwrng.read = atmel_sha204a_rng_read;
 	i2c_priv->hwrng.quality = 1024;
 
-	ret = hwrng_register(&i2c_priv->hwrng);
+	ret = devm_hwrng_register(&client->dev, &i2c_priv->hwrng);
 	if (ret)
 		dev_warn(&client->dev, "failed to register RNG (%d)\n", ret);
 
···
 
 	if (i2c_priv->hwrng.priv)
 		kfree((void *)i2c_priv->hwrng.priv);
-	hwrng_unregister(&i2c_priv->hwrng);
 
 	return 0;
 }