usb: typec: Rationalize the API for the muxes

Since with accessory modes there is no need for additional
identification when requesting a handle to the mux, we can
replace the second parameter that is passed to the
typec_mux_get() function with a pointer to alternate mode
description structure, and simply passing NULL with
accessory modes.

This change means the naming of the mux device connections
can be updated. Alternate and Accessory Modes will both be
handled with muxes named "mode-switch", and the orientation
switches will be named "orientation-switch".

Future identification of the alternate modes will be later
done using device property "svid" of the mux.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>