i40e: Drop unused completed stat

The Tx "completed" stat was part of the original rewrite for detecting
Tx hangs.  However some time ago in ixgbe I determined that we could
just use the packets stat instead.  Since then this stat was
removed from ixgbe and it serves no purpose in i40e so it can be
dropped.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_debugfs.c

@@ -560,10 +560,9 @@ static void i40e_dbg_dump_vsi_seid(struct i40e_pf *pf, int seid)
 				 vsi->tx_rings[i].tx_stats.bytes,
 				 vsi->tx_rings[i].tx_stats.restart_queue);
 			dev_info(&pf->pdev->dev,
-				 "    tx_rings[%i]: tx_stats: tx_busy = %lld, completed = %lld, tx_done_old = %lld\n",
+				 "    tx_rings[%i]: tx_stats: tx_busy = %lld, tx_done_old = %lld\n",
 				 i,
 				 vsi->tx_rings[i].tx_stats.tx_busy,
-				 vsi->tx_rings[i].tx_stats.completed,
 				 vsi->tx_rings[i].tx_stats.tx_done_old);
 			dev_info(&pf->pdev->dev,
 				 "    tx_rings[%i]: size = %i, dma = 0x%08lx\n",

drivers/net/ethernet/intel/i40e/i40e_txrx.c

@@ -346,8 +346,7 @@ static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
 		      cpu_to_le64(I40E_TX_DESC_DTYPE_DESC_DONE)))
 			break;
 
-		/* count the packet as being completed */
-		tx_ring->tx_stats.completed++;
+		/* clear next_to_watch to prevent false hangs */
 		tx_buf->next_to_watch = NULL;
 		tx_buf->time_stamp = 0;
 

drivers/net/ethernet/intel/i40e/i40e_txrx.h

@@ -134,7 +134,6 @@ struct i40e_tx_queue_stats {
 	u64 bytes;
 	u64 restart_queue;
 	u64 tx_busy;
-	u64 completed;
 	u64 tx_done_old;
 };