net: stmmac: update pci platform data to use phy_interface

The recent patch to support passive mode converter did not take care the
phy interface configuration in PCI platform data. Hence, converting all
the PCI platform data from plat->interface to plat->phy_interface as the
default mode is meant for PHY.

Fixes: 0060c878

 ("net: stmmac: implement support for passive mode converters via dt")
Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Tested-by: Tan, Tee Min <tee.min.tan@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>