net: dsa: mv88e6xxx: Enable CMODE config support for 6390X

Commit f39908d3b1c45 ('net: dsa: mv88e6xxx: Set the CMODE for mv88e6390
ports 9 & 10') added support for setting the CMODE for the 6390X family,
but only enabled it for 9290 and 6390 - and left out 6390X.

Fix support for setting the CMODE on 6390X also by assigning
mv88e6390x_port_set_cmode() to the .port_set_cmode function pointer in
mv88e6390x_ops too.

Fixes: f39908d3b1c4 ("net: dsa: mv88e6xxx: Set the CMODE for mv88e6390 ports 9 & 10")
Signed-off-by: Martin Hundebøll <mnhu@prevas.dk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -3178,6 +3178,7 @@ static const struct mv88e6xxx_ops mv88e6390x_ops = {
 	.port_set_jumbo_size = mv88e6165_port_set_jumbo_size,
 	.port_egress_rate_limiting = mv88e6097_port_egress_rate_limiting,
 	.port_pause_limit = mv88e6390_port_pause_limit,
+	.port_set_cmode = mv88e6390x_port_set_cmode,
 	.port_disable_learn_limit = mv88e6xxx_port_disable_learn_limit,
 	.port_disable_pri_override = mv88e6xxx_port_disable_pri_override,
 	.stats_snapshot = mv88e6390_g1_stats_snapshot,