net: tsec: read the phy-mode property as fallback to phy-connection-type

The two should be equivalent, but at the moment some platforms
(ls1021a-tsn.dts) use phy-mode only, which is not parsed.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
diff --git a/drivers/net/tsec.c b/drivers/net/tsec.c
index 851072c..0ce9765 100644
--- a/drivers/net/tsec.c
+++ b/drivers/net/tsec.c
@@ -884,6 +884,8 @@
 	priv->tbiaddr = tbiaddr;
 
 	phy_mode = dev_read_prop(dev, "phy-connection-type", NULL);
+	if (!phy_mode)
+		phy_mode = dev_read_prop(dev, "phy-mode", NULL);
 	if (phy_mode)
 		pdata->phy_interface = phy_get_interface_by_name(phy_mode);
 	if (pdata->phy_interface == -1)