Official TBS dvb-core patch

--- linux/drivers/media/dvb/dvb-core/dvbdev.c	2012-06-02 19:21:57.000000000 +0200
+++ linux/drivers/media/dvb/dvb-core/dvbdev.c	2015-02-28 20:52:50.324122926 +0100
@@ -68,7 +68,7 @@
 {
 	struct dvb_device *dvbdev;

-	mutex_lock(&dvbdev_mutex);
+	//mutex_lock(&dvbdev_mutex);
 	down_read(&minor_rwsem);
 	dvbdev = dvb_minors[iminor(inode)];

@@ -91,12 +91,12 @@
 		}
 		fops_put(old_fops);
 		up_read(&minor_rwsem);
-		mutex_unlock(&dvbdev_mutex);
+		//mutex_unlock(&dvbdev_mutex);
 		return err;
 	}
 fail:
 	up_read(&minor_rwsem);
-	mutex_unlock(&dvbdev_mutex);
+	//mutex_unlock(&dvbdev_mutex);
 	return -ENODEV;
 }

@@ -439,6 +439,7 @@
 	kfree(mbuf);
 	return err;
 }
+EXPORT_SYMBOL(dvb_usercopy);

 static int dvb_uevent(struct device *dev, struct kobj_uevent_env *env)
 {