pppoe: remove unnecessary checks in pppoe_flush_dev

pernet memory is guaranteed to exist when notifiers are called.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/pppoe.c b/drivers/net/pppoe.c
index c059c8d..99f031a 100644
--- a/drivers/net/pppoe.c
+++ b/drivers/net/pppoe.c
@@ -290,12 +290,6 @@
 	struct pppoe_net *pn;
 	int i;
 
-	BUG_ON(dev == NULL);
-
-	pn = pppoe_pernet(dev_net(dev));
-	if (!pn) /* already freed */
-		return;
-
 	write_lock_bh(&pn->hash_lock);
 	for (i = 0; i < PPPOE_HASH_SIZE; i++) {
 		struct pppox_sock *po = pn->hash_table[i];