tty: riscom8, fix tty refcnt

Stanse found a tty refcnt leak on one fail path in rc_transmit.
Fix that by jumping to the 'out' label.

http://stanse.fi.muni.cz/Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/char/riscom8.c

@@ -467,7 +467,7 @@ static void rc_transmit(struct riscom_board const *bp)
 			rc_out(bp, CD180_CCR, CCR_CORCHG2);
 			port->break_length = 0;
 		}
-		return;
+		goto out;
 	}
 
 	count = CD180_NFIFO;