[media] rtl2830: add parent for I2C adapter

i2c i2c-6: adapter [RTL2830 tuner I2C adapter] registered
BUG: unable to handle kernel NULL pointer dereference at 0000000000000220
IP: [<ffffffffa0002900>] i2c_register_adapter+0x130/0x390 [i2c_core]

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb-frontends/rtl2830.c

@@ -710,6 +710,7 @@ struct dvb_frontend *rtl2830_attach(const struct rtl2830_config *cfg,
 		sizeof(priv->tuner_i2c_adapter.name));
 	priv->tuner_i2c_adapter.algo = &rtl2830_tuner_i2c_algo;
 	priv->tuner_i2c_adapter.algo_data = NULL;
+	priv->tuner_i2c_adapter.dev.parent = &i2c->dev;
 	i2c_set_adapdata(&priv->tuner_i2c_adapter, priv);
 	if (i2c_add_adapter(&priv->tuner_i2c_adapter) < 0) {
 		dev_err(&i2c->dev,