net: dsa: Allow compiling out legacy support

Introduce a configuration option: CONFIG_NET_DSA_LEGACY allowing to compile out
support for the old platform device and Device Tree binding registration.
Support for these configurations is scheduled to be removed in 4.17.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 895db05..5d6475a 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -941,6 +941,26 @@ static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.set_rxnfc		= dsa_slave_set_rxnfc,
 };
 
+/* legacy way, bypassing the bridge *****************************************/
+int dsa_legacy_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid,
+		       u16 flags)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dsa_port_fdb_add(dp, addr, vid);
+}
+
+int dsa_legacy_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
+		       struct net_device *dev,
+		       const unsigned char *addr, u16 vid)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+
+	return dsa_port_fdb_del(dp, addr, vid);
+}
+
 static const struct net_device_ops dsa_slave_netdev_ops = {
 	.ndo_open	 	= dsa_slave_open,
 	.ndo_stop		= dsa_slave_close,