drivers: mdio: Update the change from migrating FSP 6.0.0

Midify to use ``p_phy_lsi_cfg_list`` in ``ether_phy_cfg.p_extend``
instead of using ``phy_lsi_type`` and ``phy_lsi_address``
in ``ether_phy_cfg``. Update for mdio_renesas_ra

Signed-off-by: Khoa Nguyen <khoa.nguyen.xh@renesas.com>