net: dsa: mv88e6xxx: Refactor egress rate limiting

There are two different rate limiting configurations, depending on the
switch generation. Refactor this into ops.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/dsa/mv88e6xxx/port.c b/drivers/net/dsa/mv88e6xxx/port.c
index a739129..d22c7b0 100644
--- a/drivers/net/dsa/mv88e6xxx/port.c
+++ b/drivers/net/dsa/mv88e6xxx/port.c
@@ -621,6 +621,18 @@ int mv88e6165_port_jumbo_config(struct mv88e6xxx_chip *chip, int port)
 	return mv88e6xxx_port_write(chip, port, PORT_CONTROL_2, reg);
 }
 
+/* Offset 0x09: Port Rate Control */
+
+int mv88e6095_port_egress_rate_limiting(struct mv88e6xxx_chip *chip, int port)
+{
+	return mv88e6xxx_port_write(chip, port, PORT_RATE_CONTROL, 0x0000);
+}
+
+int mv88e6097_port_egress_rate_limiting(struct mv88e6xxx_chip *chip, int port)
+{
+	return mv88e6xxx_port_write(chip, port, PORT_RATE_CONTROL, 0x0001);
+}
+
 /* Offset 0x0f: Port Ether type */
 
 int mv88e6351_port_set_ether_type(struct mv88e6xxx_chip *chip, int port,