net: dsa: lantiq_gswip: Remove dead code from gswip_add_single_port_br()

The port validation in gswip_add_single_port_br() is superfluous and
can be omitted.
Suggested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Link: https://lore.kernel.org/r/20240611135434.3180973-11-ms@dev.tdt.deSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/lantiq_gswip.c

@@ -655,14 +655,8 @@ static int gswip_add_single_port_br(struct gswip_priv *priv, int port, bool add)
 	struct gswip_pce_table_entry vlan_active = {0,};
 	struct gswip_pce_table_entry vlan_mapping = {0,};
 	unsigned int cpu_port = priv->hw_info->cpu_port;
-	unsigned int max_ports = priv->hw_info->max_ports;
 	int err;
 
-	if (port >= max_ports) {
-		dev_err(priv->dev, "single port for %i supported\n", port);
-		return -EIO;
-	}
-
 	vlan_active.index = port + 1;
 	vlan_active.table = GSWIP_TABLE_ACTIVE_VLAN;
 	vlan_active.key[0] = 0; /* vid */