net: dsa: store CPU port pointer in the tree

A dsa_switch_tree instance holds a dsa_switch pointer and a port index
to identify the switch port to which the CPU is attached.

Now that the DSA layer has a dsa_port structure to hold this data, use
it to point the switch CPU port.

This patch simply substitutes s/dst->cpu_switch/dst->cpu_dp->ds/ and
s/dst->cpu_port/dst->cpu_dp->index/.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/b53/b53_common.c

@@ -1344,7 +1344,7 @@ EXPORT_SYMBOL(b53_fdb_dump);
 int b53_br_join(struct dsa_switch *ds, int port, struct net_device *br)
 {
 	struct b53_device *dev = ds->priv;
-	s8 cpu_port = ds->dst->cpu_port;
+	s8 cpu_port = ds->dst->cpu_dp->index;
 	u16 pvlan, reg;
 	unsigned int i;
 
@@ -1390,7 +1390,7 @@ void b53_br_leave(struct dsa_switch *ds, int port, struct net_device *br)
 {
 	struct b53_device *dev = ds->priv;
 	struct b53_vlan *vl = &dev->vlans[0];
-	s8 cpu_port = ds->dst->cpu_port;
+	s8 cpu_port = ds->dst->cpu_dp->index;
 	unsigned int i;
 	u16 pvlan, reg, pvid;