net: phylink: Add struct phylink_config to PHYLINK API

net: phylink: Add struct phylink_config to PHYLINK API

The phylink_config structure will encapsulate a pointer to a struct
device and the operation type requested for this instance of PHYLINK.
This patch does not make any functional changes, it just transitions the
PHYLINK internals and all its users to the new API.

A pointer to a phylink_config structure will be passed to
phylink_create() instead of the net_device directly. Also, the same
phylink_config pointer will be passed back to all phylink_mac_ops
callbacks instead of the net_device. Using this mechanism, a PHYLINK
user can get the original net_device using a structure such as
'to_net_dev(config->dev)' or directly the structure containing the
phylink_config using a container_of call.

At the moment, only the PHYLINK_NETDEV is defined as a valid operation
type for PHYLINK. In this mode, a valid reference to a struct device
linked to the original net_device should be passed to PHYLINK through
the phylink_config structure.

This API changes is mainly driven by the necessity of adding a new
operation type in PHYLINK that disconnects the phy_device from the
net_device and also works when the net_device is lacking.

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>