Adding functions that USB hub code can use to inform the
Type-C class about connected USB devices.

Once taken into use, it will allow the Type-C port drivers
to power off components that are not needed, for example if
USB2 device is enumerated, everything that is only relevant
for USB3 (retimers, etc.), can be powered off.

This will also create a symlink "typec" for the USB devices
pointing to the USB Type-C partner device.
Suggested-by: Benson Leung <bleung@chromium.org>
Tested-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20231011105825.320062-2-heikki.krogerus@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>