net: skge: 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/skge.c

@@ -876,6 +876,7 @@ static int skge_set_eeprom(struct net_device *dev, struct ethtool_eeprom *eeprom
 }
 
 static const struct ethtool_ops skge_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_USECS,
 	.get_drvinfo	= skge_get_drvinfo,
 	.get_regs_len	= skge_get_regs_len,
 	.get_regs	= skge_get_regs,