wireless: Create 'device' symlink in sysfs

Some network interfaces of the wireless drivers lack the 'device'
symlink in sysfs.
This patch lets the drivers create the links.

Signed-off-by: Masakazu Mokuno <mokuno@sm.sony.co.jp>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
index bb08f0b..e1f0660 100644
--- a/drivers/net/wireless/libertas/main.c
+++ b/drivers/net/wireless/libertas/main.c
@@ -1565,6 +1565,7 @@
 	rtap_dev->hard_start_xmit = lbs_rtap_hard_start_xmit;
 	rtap_dev->set_multicast_list = lbs_set_multicast_list;
 	rtap_dev->priv = priv;
+	SET_NETDEV_DEV(rtap_dev, priv->dev->dev.parent);
 
 	ret = register_netdev(rtap_dev);
 	if (ret) {