Merge branch 'devlink-controller-external-info' into next

Parav Pandit  says:

====================

For certain devlink port flavours controller number and optionally external=
 attributes are reported by the kernel.

(a) controller number indicates that a given port belong to which local or =
external controller.
(b) external port attribute indicates that if a given port is for external =
or local controller.

This short series shows this attributes to user.

====================

Signed-off-by: David Ahern <dsahern@gmail.com>