drivers: net: xilinx_emaclite: Add missing parameter kerneldoc

The txqueue parameter to the watchdog callback is unused in this
driver. But it still needs to be documented.
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/xilinx/xilinx_emaclite.c

@@ -518,6 +518,7 @@ static int xemaclite_set_mac_address(struct net_device *dev, void *address)
 /**
  * xemaclite_tx_timeout - Callback for Tx Timeout
  * @dev:	Pointer to the network device
+ * @txqueue:	Unused
  *
  * This function is called when Tx time out occurs for Emaclite device.
  */