usb: typec: More API for cable handling

Thunderbolt 3, and probable USB4 too, will need to be able
to get details about the cables. Adding typec_cable_get()
function that the alternate mode drivers can use to gain
access to gain access to the cable.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191230142611.24921-4-heikki.krogerus@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>