Introducing a simple bus for the alternate modes. Bus allows
binding drivers to the discovered alternate modes the
partners support.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>