net: stmmac: rk: remove of_get_phy_mode()

devm_stmmac_probe_config_dt() already gets the PHY mode from firmware,
which is stored in plat_dat->phy_interface. Therefore, we don't need to
get it in platform code.

Set bsp_priv->phy_iface from plat->phy_interface.

Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1tsIGi-005uzx-3p@rmk-PC.armlinux.org.uk
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c

@@ -1503,7 +1503,7 @@ static struct rk_priv_data *rk_gmac_setup(struct platform_device *pdev,
 	if (!bsp_priv)
 		return ERR_PTR(-ENOMEM);
 
-	of_get_phy_mode(dev->of_node, &bsp_priv->phy_iface);
+	bsp_priv->phy_iface = plat->phy_interface;
 	bsp_priv->ops = ops;
 
 	/* Some SoCs have multiple MAC controllers, which need