i40e: remove fake support of rx-frames-irq

Since we never support this feature for I40E driver, we don't have to
display the value when using 'ethtool -c eth0'.

Before this patch applied, the rx-frames-irq is 256 which is consistent
with tx-frames-irq. Apparently it could mislead users.
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20231213184406.1306602-1-anthony.l.nguyen@intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/intel/i40e/i40e_ethtool.c

@@ -2893,7 +2893,6 @@ static int __i40e_get_coalesce(struct net_device *netdev,
 	struct i40e_vsi *vsi = np->vsi;
 
 	ec->tx_max_coalesced_frames_irq = vsi->work_limit;
-	ec->rx_max_coalesced_frames_irq = vsi->work_limit;
 
 	/* rx and tx usecs has per queue value. If user doesn't specify the
 	 * queue, return queue 0's value to represent.
@@ -3027,7 +3026,7 @@ static int __i40e_set_coalesce(struct net_device *netdev,
 	struct i40e_pf *pf = vsi->back;
 	int i;
 
-	if (ec->tx_max_coalesced_frames_irq || ec->rx_max_coalesced_frames_irq)
+	if (ec->tx_max_coalesced_frames_irq)
 		vsi->work_limit = ec->tx_max_coalesced_frames_irq;
 
 	if (queue < 0) {
@@ -5784,7 +5783,7 @@ static const struct ethtool_ops i40e_ethtool_recovery_mode_ops = {
 
 static const struct ethtool_ops i40e_ethtool_ops = {
 	.supported_coalesce_params = ETHTOOL_COALESCE_USECS |
-				     ETHTOOL_COALESCE_MAX_FRAMES_IRQ |
+				     ETHTOOL_COALESCE_TX_MAX_FRAMES_IRQ |
 				     ETHTOOL_COALESCE_USE_ADAPTIVE |
 				     ETHTOOL_COALESCE_RX_USECS_HIGH |
 				     ETHTOOL_COALESCE_TX_USECS_HIGH,