driver core: bus: Fix a potential double free

The .release function of driver_ktype is 'driver_release()'.
This function frees the container_of this kobject.

So, this memory must not be freed explicitly in the error handling path of
'bus_add_driver()'. Otherwise a double free will occur.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>