net: dsa: mv88e6xxx: allocate the number of ports

The current code allocates DSA_MAX_PORTS ports for a Marvell dsa_switch
structure. Provide the exact number of ports so the corresponding
ds->num_ports is accurate.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -4286,7 +4286,7 @@ static int mv88e6xxx_register_switch(struct mv88e6xxx_chip *chip)
 	struct device *dev = chip->dev;
 	struct dsa_switch *ds;
 
-	ds = dsa_switch_alloc(dev, DSA_MAX_PORTS);
+	ds = dsa_switch_alloc(dev, mv88e6xxx_num_ports(chip));
 	if (!ds)
 		return -ENOMEM;