be2net: cleanup multicast_set cmd to avoid mc_list copy

Cleanup multicast_set method to avoid an extra copy of mc_list
 and unwanted promiscuos sets to BE.

Signed-off-by: Sathya Perla <sathyap@serverengines.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/benet/be.h b/drivers/net/benet/be.h
index ef5be13..94b75cb 100644
--- a/drivers/net/benet/be.h
+++ b/drivers/net/benet/be.h
@@ -274,6 +274,7 @@
 
 	struct be_link_info link;
 	u32 port_num;
+	bool promiscuous;
 };
 
 extern struct ethtool_ops be_ethtool_ops;