bridge: use time_before() in br_fdb_cleanup()

In br_fdb_cleanup() next_timer and this_timer are in jiffies, so they
should be compared using the time_after() macro.
Signed-off-by: Fabio Checconi <fabio@gandalf.sssup.it>
Signed-off-by: Stephen Hemminger <stephen.hemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_fdb.c

@@ -136,7 +136,7 @@ void br_fdb_cleanup(unsigned long _data)
 			this_timer = f->ageing_timer + delay;
 			if (time_before_eq(this_timer, jiffies))
 				fdb_delete(f);
-			else if (this_timer < next_timer)
+			else if (time_before(this_timer, next_timer))
 				next_timer = this_timer;
 		}
 	}