TTY: HVC, add tty_port

And use kref from that. This means we need tty_port->ops->destruct to
properly free the structure. This is what destroy_hvc_struct used to
do so we leverage that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
index c335a14..926d9e4 100644
--- a/drivers/tty/hvc/hvc_console.h
+++ b/drivers/tty/hvc/hvc_console.h
@@ -46,6 +46,7 @@
 #define HVC_ALLOC_TTY_ADAPTERS	8
 
 struct hvc_struct {
+	struct tty_port port;
 	spinlock_t lock;
 	int index;
 	struct tty_struct *tty;
@@ -61,7 +62,6 @@
 	struct winsize ws;
 	struct work_struct tty_resize;
 	struct list_head next;
-	struct kref kref; /* ref count & hvc_struct lifetime */
 };
 
 /* implemented by a low level driver */