drivers/net: replace BUG() with BUG_ON() if possible

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c
index 5b07dd8..5981deb 100644
--- a/drivers/net/pppol2tp.c
+++ b/drivers/net/pppol2tp.c
@@ -1238,8 +1238,7 @@
 	struct pppol2tp_session *session;
 	struct sock *sk;
 
-	if (tunnel == NULL)
-		BUG();
+	BUG_ON(tunnel == NULL);
 
 	PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO,
 	       "%s: closing all sessions...\n", tunnel->name);