TTY: use tty_port_register_device

Currently we have no way to assign tty->port while performing tty
installation. There are two ways to provide the link tty_struct =>
tty_port. Either by calling tty_port_install from tty->ops->install or
tty_port_register_device called instead of tty_register_device when
the device is being set up after connected.

In this patch we modify most of the drivers to do the latter. When the
drivers use tty_register_device and we have tty_port already, we
switch to tty_port_register_device. So we have the tty_struct =>
tty_port link for free for those.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/isicom.c b/drivers/tty/isicom.c
index d593a7d..99cf22e 100644
--- a/drivers/tty/isicom.c
+++ b/drivers/tty/isicom.c
@@ -1611,7 +1611,8 @@
 		goto errunri;
 
 	for (index = 0; index < board->port_count; index++)
-		tty_register_device(isicom_normal, board->index * 16 + index,
+		tty_port_register_device(&board->ports[index].port,
+				isicom_normal, board->index * 16 + index,
 				&pdev->dev);
 
 	return 0;