Add basic support for devlink at the device level. The callbacks of
struct devlink_ops will be implemented next.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20221130174658.29282-2-mailhol.vincent@wanadoo.frSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>