bridge: Fix timer typo that may render snooping less effective

In a couple of spots where we are supposed to modify the port
group timer (p->timer) we instead modify the bridge interface
group timer (mp->timer).

The effect of this is mostly harmless.  However, it can cause
port subscriptions to be longer than they should be, thus making
snooping less effective.

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 fdbd41c..c558274 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1178,7 +1178,7 @@
 		if (timer_pending(&p->timer) ?
 		    time_after(p->timer.expires, now + max_delay) :
 		    try_to_del_timer_sync(&p->timer) >= 0)
-			mod_timer(&mp->timer, now + max_delay);
+			mod_timer(&p->timer, now + max_delay);
 	}
 
 out:
@@ -1249,7 +1249,7 @@
 		if (timer_pending(&p->timer) ?
 		    time_after(p->timer.expires, now + max_delay) :
 		    try_to_del_timer_sync(&p->timer) >= 0)
-			mod_timer(&mp->timer, now + max_delay);
+			mod_timer(&p->timer, now + max_delay);
 	}
 
 out: