wl3501_cs: Remove unnecessary NULL check

In wl3501_detach(), link->priv is checked for a NULL value before being
passed to free_netdev(). However, it cannot be NULL at this point as it
has already been passed to other functions, so just remove the check.

Addresses-Coverity: CID 710499: Null pointer dereferences (REVERSE_INULL)
Signed-off-by: NAlex Dewar <alex.dewar90@gmail.com>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200926174558.9436-1-alex.dewar90@gmail.com

drivers/net/wireless/wl3501_cs.c

@@ -1433,9 +1433,7 @@ static void wl3501_detach(struct pcmcia_device *link)
 	wl3501_release(link);
 
 	unregister_netdev(dev);
-
-	if (link->priv)
-		free_netdev(link->priv);
+	free_netdev(dev);
 }
 
 static int wl3501_get_name(struct net_device *dev, struct iw_request_info *info,