net: vmxnet3: convert to use .get_rx_ring_count

Convert the vmxnet3 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/vmxnet3/vmxnet3_ethtool.c

···
 	return 0;
 }
 
-static int
-vmxnet3_get_rxnfc(struct net_device *netdev, struct ethtool_rxnfc *info,
-		  u32 *rules)
+static u32 vmxnet3_get_rx_ring_count(struct net_device *netdev)
 {
 	struct vmxnet3_adapter *adapter = netdev_priv(netdev);
-	int err = 0;
 
-	switch (info->cmd) {
-	case ETHTOOL_GRXRINGS:
-		info->data = adapter->num_rx_queues;
-		break;
-	default:
-		err = -EOPNOTSUPP;
-		break;
-	}
-
-	return err;
+	return adapter->num_rx_queues;
 }
 
 #ifdef VMXNET3_RSS
···
 	.get_ethtool_stats = vmxnet3_get_ethtool_stats,
 	.get_ringparam     = vmxnet3_get_ringparam,
 	.set_ringparam     = vmxnet3_set_ringparam,
-	.get_rxnfc         = vmxnet3_get_rxnfc,
+	.get_rx_ring_count = vmxnet3_get_rx_ring_count,
 #ifdef VMXNET3_RSS
 	.get_rxfh_indir_size = vmxnet3_get_rss_indir_size,
 	.get_rxfh          = vmxnet3_get_rss,