qlcnic: guard __vlan_find_dev_deep() by rcu_read_lock

rcu_read_lock was missing here

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Sony Chacko <sony.chacko@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
index 137ca13..3655ca2 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -3186,12 +3186,14 @@
 
 	qlcnic_config_indev_addr(adapter, netdev, event);
 
+	rcu_read_lock();
 	for_each_set_bit(vid, adapter->vlans, VLAN_N_VID) {
 		dev = __vlan_find_dev_deep(netdev, vid);
 		if (!dev)
 			continue;
 		qlcnic_config_indev_addr(adapter, dev, event);
 	}
+	rcu_read_unlock();
 }
 
 static int qlcnic_netdev_event(struct notifier_block *this,