nfp: ethtool: fix the display error of `ethtool -m DEVNAME`

The port flag isn't set to `NFP_PORT_CHANGED` when using
`ethtool -m DEVNAME` before, so the port state (e.g. interface)
cannot be updated. Therefore, it caused that `ethtool -m DEVNAME`
sometimes cannot read the correct information.

E.g. `ethtool -m DEVNAME` cannot work when load driver before plug
in optical module, as the port interface is still NONE without port
update.

Now update the port state before sending info to NIC to ensure that
port interface is correct (latest state).

Fixes: 61f7c6f448 ("nfp: implement ethtool get module EEPROM")
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Yu Xiao <yu.xiao@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20220802093355.69065-1-simon.horman@corigine.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/netronome/nfp/nfp_net_ethtool.c

@@ -1395,6 +1395,8 @@ nfp_port_get_module_info(struct net_device *netdev,
 	u8 data;
 
 	port = nfp_port_from_netdev(netdev);
+	/* update port state to get latest interface */
+	set_bit(NFP_PORT_CHANGED, &port->flags);
 	eth_port = nfp_port_get_eth_port(port);
 	if (!eth_port)
 		return -EOPNOTSUPP;