Failure to initialize if_type means that grub2/efinet sends
a bogus arp request. It therefore gets no response. On Raspberry Pi 3B+
this leads to a pause at:
lan78xx_eth Waiting for PHY auto negotiation to complete....... done
lan78xx_eth Waiting for PHY auto negotiation to complete....... done
Signed-off-by: Andrew Thomas <andrew.thomas@oracle.com> Acked-by: Joe Hershberger <joe.hershberger@ni.com>