MN10300: Fix MN10300's serial port driver to get at its tty_struct

Fix MN10300's serial port driver to get at its tty_struct as this moved
from struct uart_info into struct tty_port in patch:
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/mn10300/kernel/mn10300-serial.c

@@ -392,7 +392,7 @@ static int mask_test_and_clear(volatile u8 *ptr, u8 mask)
 static void mn10300_serial_receive_interrupt(struct mn10300_serial_port *port)
 {
 	struct uart_icount *icount = &port->uart.icount;
-	struct tty_struct *tty = port->uart.info->tty;
+	struct tty_struct *tty = port->uart.info->port.tty;
 	unsigned ix;
 	int count;
 	u8 st, ch, push, status, overrun;