net: dsa: sja1105: error out on unsupported PHY mode

The driver continues probing when a port is configured for an
unsupported PHY interface type, instead it should stop.

Fixes: 8aa9ebccae87 ("net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/sja1105/sja1105_main.c

@@ -207,6 +207,7 @@ static int sja1105_init_mii_settings(struct sja1105_private *priv,
 		default:
 			dev_err(dev, "Unsupported PHY mode %s!\n",
 				phy_modes(ports[i].phy_mode));
+			return -EINVAL;
 		}
 
 		/* Even though the SerDes port is able to drive SGMII autoneg