net: thunder: convert to use .get_rx_ring_count

Convert the Cavium Thunder NIC VF driver to use the new .get_rx_ring_count
ethtool operation instead of implementing .get_rxnfc solely for handling
ETHTOOL_GRXRINGS command. This simplifies the code by removing the
switch statement and replacing it with a direct return of the queue
count.

The new callback provides the same functionality in a more direct way,
following the ongoing ethtool API modernization.

Signed-off-by: Breno Leitao <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/ethernet/cavium/thunder/nicvf_ethtool.c

···
 	return 0;
 }
 
-static int nicvf_get_rxnfc(struct net_device *dev,
-			   struct ethtool_rxnfc *info, u32 *rules)
+static u32 nicvf_get_rx_ring_count(struct net_device *dev)
 {
 	struct nicvf *nic = netdev_priv(dev);
-	int ret = -EOPNOTSUPP;
 
-	switch (info->cmd) {
-	case ETHTOOL_GRXRINGS:
-		info->data = nic->rx_queues;
-		ret = 0;
-		break;
-	default:
-		break;
-	}
-	return ret;
+	return nic->rx_queues;
 }
 
 static int nicvf_set_rxfh_fields(struct net_device *dev,
···
 	.get_coalesce		= nicvf_get_coalesce,
 	.get_ringparam		= nicvf_get_ringparam,
 	.set_ringparam		= nicvf_set_ringparam,
-	.get_rxnfc		= nicvf_get_rxnfc,
+	.get_rx_ring_count	= nicvf_get_rx_ring_count,
 	.get_rxfh_key_size	= nicvf_get_rxfh_key_size,
 	.get_rxfh_indir_size	= nicvf_get_rxfh_indir_size,
 	.get_rxfh		= nicvf_get_rxfh,