net: ixgbevf: 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/intel/ixgbevf/ethtool.c

@@ -968,6 +968,7 @@ static int ixgbevf_set_priv_flags(struct net_device *netdev, u32 priv_flags)
 }
 
 static const struct ethtool_ops ixgbevf_ethtool_ops = {
+	.supported_coalesce_params = ETHTOOL_COALESCE_USECS,
 	.get_drvinfo		= ixgbevf_get_drvinfo,
 	.get_regs_len		= ixgbevf_get_regs_len,
 	.get_regs		= ixgbevf_get_regs,