drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c: remove unnecessary null test before debugfs_remove_recursive

Fix checkpatch warning:
"WARNING: debugfs_remove_recursive(NULL) is safe this check is probably not required"

Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -6637,8 +6637,7 @@ static void remove_one(struct pci_dev *pdev)
 			if (adapter->port[i]->reg_state == NETREG_REGISTERED)
 				unregister_netdev(adapter->port[i]);
 
-		if (adapter->debugfs_root)
-			debugfs_remove_recursive(adapter->debugfs_root);
+		debugfs_remove_recursive(adapter->debugfs_root);
 
 		/* If we allocated filters, free up state associated with any
 		 * valid filters ...