vt: delete unneeded function unbind_con_driver

Now there is no place use unbind_con_driver,
and we can achieve unbind_con_driver's function
with do_unbind_con_driver easily, so just delete
it to reduce code size and duplication.
Signed-off-by: NWang YanQing <udknight@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/vt.c

@@ -3116,34 +3116,6 @@ static int con_is_graphics(const struct consw *csw, int first, int last)
 	return retval;
 }
 
-/**
- * unbind_con_driver - unbind a console driver
- * @csw: pointer to console driver to unregister
- * @first: first in range of consoles that @csw should be unbound from
- * @last: last in range of consoles that @csw should be unbound from
- * @deflt: should next bound console driver be default after @csw is unbound?
- *
- * To unbind a driver from all possible consoles, pass 0 as @first and
- * %MAX_NR_CONSOLES as @last.
- *
- * @deflt controls whether the console that ends up replacing @csw should be
- * the default console.
- *
- * RETURNS:
- * -ENODEV if @csw isn't a registered console driver or can't be unregistered
- * or 0 on success.
- */
-int unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
-{
-	int retval;
-
-	console_lock();
-	retval = do_unbind_con_driver(csw, first, last, deflt);
-	console_unlock();
-	return retval;
-}
-EXPORT_SYMBOL(unbind_con_driver);
-
 /* unlocked version of unbind_con_driver() */
 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
 {

include/linux/vt_kern.h

@@ -133,8 +133,6 @@ void change_console(struct vc_data *new_vc);
 void reset_vc(struct vc_data *vc);
 extern int do_unbind_con_driver(const struct consw *csw, int first, int last,
 			     int deflt);
-extern int unbind_con_driver(const struct consw *csw, int first, int last,
-			     int deflt);
 int vty_init(const struct file_operations *console_fops);
 
 static inline bool vt_force_oops_output(struct vc_data *vc)