net: cadence: macb: add ethtool nway_reset support

Wire phy_ethtool_nway_reset() as the .nway_reset ethtool operation,
allowing userspace to restart PHY autonegotiation via 'ethtool -r'.

Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>

Author: nbuchwitz

drivers/net/ethernet/cadence/macb_main.c

@@ -3912,6 +3912,7 @@ static const struct ethtool_ops gem_ethtool_ops = {
 	.set_ringparam		= macb_set_ringparam,
 	.get_rxnfc			= gem_get_rxnfc,
 	.set_rxnfc			= gem_set_rxnfc,
+	.nway_reset		= phy_ethtool_nway_reset,
 };
 
 static int macb_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)