net: phy: intel-xway: add support for PHY LEDs

The intel-xway PHY driver predates the PHY LED framework and currently
initializes all LED pins to equal default values.

Add PHY LED functions to the drivers and don't set default values if
LEDs are defined in device tree.

According the datasheets 3 LEDs are supported on all Intel XWAY PHYs.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/81f4717ab9acf38f3239727a4540ae96fd01109b.1728558223.git.daniel@makrotopia.org


Signed-off-by: Paolo Abeni <pabeni@redhat.com>