Driver core: convert tty core to use struct device

Converts from using struct "class_device" to "struct device" making
everything show up properly in /sys/devices/ with symlinks from the
/sys/class directory.

Also fixes up the isdn drivers that were putting something in the class
device's directory.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/isdn/gigaset/gigaset.h b/drivers/isdn/gigaset/gigaset.h
index 884bd72..06298cc 100644
--- a/drivers/isdn/gigaset/gigaset.h
+++ b/drivers/isdn/gigaset/gigaset.h
@@ -444,7 +444,7 @@
 	struct gigaset_driver *driver;
 	unsigned minor_index;
 	struct device *dev;
-	struct class_device *class;
+	struct device *tty_dev;
 
 	const struct gigaset_ops *ops;