staging: dgnc: remove useless variable 'ch_intr_tx'

The 'ch_intr_tx' variable was used only for increasing.
So the 'ch_intr_tx' variable is not useful for this driver.

Signed-off-by: Daeseok Youn <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/dgnc/dgnc_cls.c

···
 			/* Transfer data (if any) from Write Queue -> UART. */
 			spin_lock_irqsave(&ch->ch_lock, flags);
 			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
-			ch->ch_intr_tx++;
 			spin_unlock_irqrestore(&ch->ch_lock, flags);
 			cls_copy_data_from_queue_to_uart(ch);
 		}

drivers/staging/dgnc/dgnc_driver.h

···
 	ulong		ch_xon_sends;	/* Count of xons transmitted */
 	ulong		ch_xoff_sends;	/* Count of xoffs transmitted */
 
-	ulong		ch_intr_tx;	/* Count of interrupts */
 	ulong		ch_intr_rx;	/* Count of interrupts */
 
 	/* /proc/<board>/<channel> entries */

drivers/staging/dgnc/dgnc_neo.c

···
 		}
 
 		if (isr & UART_IIR_THRI) {
-			ch->ch_intr_tx++;
 			/* Transfer data (if any) from Write Queue -> UART. */
 			spin_lock_irqsave(&ch->ch_lock, flags);
 			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
···
 	}
 
 	if (linestatus & UART_LSR_THRE) {
-		ch->ch_intr_tx++;
 		spin_lock_irqsave(&ch->ch_lock, flags);
 		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 		spin_unlock_irqrestore(&ch->ch_lock, flags);
···
 		/* Transfer data (if any) from Write Queue -> UART. */
 		neo_copy_data_from_queue_to_uart(ch);
 	} else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
-		ch->ch_intr_tx++;
 		spin_lock_irqsave(&ch->ch_lock, flags);
 		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 		spin_unlock_irqrestore(&ch->ch_lock, flags);