net: mvneta: reject unsupported coalescing params

Set ethtool_ops->supported_coalesce_params to let
the core reject unsupported coalescing parameters.

This driver did not previously reject unsupported parameters.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvneta.c

@@ -4838,6 +4838,8 @@ static const struct net_device_ops mvneta_netdev_ops = {
 };
 
 static const struct ethtool_ops mvneta_eth_tool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_RX_USECS |
+				     ETHTOOL_COALESCE_MAX_FRAMES,
 	.nway_reset	= mvneta_ethtool_nway_reset,
 	.get_link       = ethtool_op_get_link,
 	.set_coalesce   = mvneta_ethtool_set_coalesce,