bridge: Allow multicast snooping to be disabled before ifup

Currently you cannot disable multicast snooping while a device is
down.  There is no good reason for this restriction and this patch
removes it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 85afcda..eb5b256 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1728,13 +1728,9 @@
 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
 {
 	struct net_bridge_port *port;
-	int err = -ENOENT;
+	int err = 0;
 
 	spin_lock(&br->multicast_lock);
-	if (!netif_running(br->dev))
-		goto unlock;
-
-	err = 0;
 	if (br->multicast_disabled == !val)
 		goto unlock;
 
@@ -1742,6 +1738,9 @@
 	if (br->multicast_disabled)
 		goto unlock;
 
+	if (!netif_running(br->dev))
+		goto unlock;
+
 	if (br->mdb) {
 		if (br->mdb->old) {
 			err = -EEXIST;