staging: dgnc: remove useless error value assignment

The "result" variable in dgnc_get_mstat() was initialized with
"-EIO". But if the "ch" is not null, "result" will be set to zero
and if the "ch" is null, dgnc_get_mstat() will return "-ENXIO" as
an error. So "-EIO" error value was useless in dgnc_get_mstat().
Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/dgnc/dgnc_tty.c

@@ -1979,7 +1979,7 @@ static void dgnc_tty_send_xchar(struct tty_struct *tty, char c)
 static inline int dgnc_get_mstat(struct channel_t *ch)
 {
 	unsigned char mstat;
-	int result = -EIO;
+	int result = 0;
 	unsigned long flags;
 
 	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
@@ -1991,8 +1991,6 @@ static inline int dgnc_get_mstat(struct channel_t *ch)
 
 	spin_unlock_irqrestore(&ch->ch_lock, flags);
 
-	result = 0;
-
 	if (mstat & UART_MCR_DTR)
 		result |= TIOCM_DTR;
 	if (mstat & UART_MCR_RTS)