[media] ngene: preventing dereferencing a NULL pointer

As reported by smatch:
	drivers/media/pci/ngene/ngene-core.c:1529 init_channel() error: we previously assumed 'chan->fe' could be null (see line 1521)
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/pci/ngene/ngene-core.c

@@ -1526,10 +1526,12 @@ static int init_channel(struct ngene_channel *chan)
 	if (chan->fe2) {
 		if (dvb_register_frontend(adapter, chan->fe2) < 0)
 			goto err;
-		chan->fe2->tuner_priv = chan->fe->tuner_priv;
-		memcpy(&chan->fe2->ops.tuner_ops,
-		       &chan->fe->ops.tuner_ops,
-		       sizeof(struct dvb_tuner_ops));
+		if (chan->fe) {
+			chan->fe2->tuner_priv = chan->fe->tuner_priv;
+			memcpy(&chan->fe2->ops.tuner_ops,
+			       &chan->fe->ops.tuner_ops,
+			       sizeof(struct dvb_tuner_ops));
+		}
 	}
 
 	if (chan->has_demux) {