usb: typec: Add attribute file showing the supported USB modes of the port

This attribute file, named "usb_capability", will show the
supported USB modes, which are USB 2.0, USB 3.2 and USB4.
These modes are defined in the USB Type-C (R2.0) and USB
Power Delivery (R3.0 V2.0) Specifications.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20241016131834.898599-2-heikki.krogerus@linux.intel.com


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