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/isdn/gigaset/interface.c b/drivers/isdn/gigaset/interface.c
index f9aab74..67abf3f 100644
--- a/drivers/isdn/gigaset/interface.c
+++ b/drivers/isdn/gigaset/interface.c
@@ -524,7 +524,8 @@
 	tasklet_init(&cs->if_wake_tasklet, if_wake, (unsigned long) cs);
 
 	mutex_lock(&cs->mutex);
-	cs->tty_dev = tty_register_device(drv->tty, cs->minor_index, NULL);
+	cs->tty_dev = tty_port_register_device(&cs->port, drv->tty,
+			cs->minor_index, NULL);
 
 	if (!IS_ERR(cs->tty_dev))
 		dev_set_drvdata(cs->tty_dev, cs);