serial: use tty_port

Switch the serial_core based drivers to use the new tty_port structure.
We can't quite use all of it yet because of the dynamically allocated
extras in the serial_core layer.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index ac4f20c..ce948b6 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1287,7 +1287,7 @@
 static void
 receive_chars(struct uart_8250_port *up, unsigned int *status)
 {
-	struct tty_struct *tty = up->port.info->tty;
+	struct tty_struct *tty = up->port.info->port.tty;
 	unsigned char ch, lsr = *status;
 	int max_count = 256;
 	char flag;