dvb: fix tuner registration without CONFIG_DVB_NET

Ever since linux-3.1, my DVB tuners have been non-functional. This turns out to be due to a bug in with this chunk of code inside linux/drivers/media/video/videobuf-dvb.c:

        /* register network adapter */
        dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
        if (dvb->net.dvbdev == NULL) {
                result = -ENOMEM;
                goto fail_fe_conn;
        }

The problem is, dvb_net_init() doesn't do anything for the case where CONFIG_DVB_NET is not set.
And the code in videobuf-dvb.c treats this as a fatal error.

The patch below (linux-3.2.6) fixes the regression.

---
Patch is also attached to bypass email mangling.

--- linux-3.2.6/drivers/media/video/videobuf-dvb.c 2012-02-13 14:17:29.000000000
-0500
+++ linux/drivers/media/video/videobuf-dvb.c 2012-02-18 13:21:42.422716047 -0500
@@ -226,9 +226,10 @@
}

/* register network adapter */
- dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
- if (dvb->net.dvbdev == NULL) {
- result = -ENOMEM;
+ result = dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
+ if (result < 0) {
+ printk(KERN_WARNING "%s: dvb_net_init failed (errno = %d)\n",
+ dvb->name, result);
goto fail_fe_conn;
}
return 0;

@@ -226,9 +226,10 @@
 	}
 
 	/* register network adapter */
-	dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
-	if (dvb->net.dvbdev == NULL) {
-		result = -ENOMEM;
+	result = dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
+	if (result < 0) {
+		printk(KERN_WARNING "%s: dvb_net_init failed (errno = %d)\n",
+		       dvb->name, result);
 		goto fail_fe_conn;
 	}
 	return 0;