drivers: net: ethernet: xilinx: xilinx_emaclite: Compatible with 'xlnx, xps-ethernetlite-2.00.b' for QEMU using

When use current latest upstream qemu (current version: 2.1.2), need let
driver compatible with 'xlnx,xps-ethernetlite-2.00.b', or can not find
net device in microblaze qemu. Related QEMU commands under fedora 20:

  yum install libvirt
  yum install tunctl
  tunctl -b
  ip link set tap0 up
  brctl addif virbr0 tap0
  ./microblaze-softmmu/qemu-system-microblaze -M petalogix-s3adsp1800 \
    -kernel ../linux-stable.microblaze/arch/microblaze/boot/linux.bin \
    -no-reboot -append "console=ttyUL0,115200 doreboot" -nographic \
    -net nic,vlan=0,model=xlnx.xps-ethernetlite,macaddr=00:16:35:AF:94:00 \
    -net tap,vlan=0,ifname=tap0,script=no,downscript=no

  in microblaze qemu bash (guest machine):

    ifconfig eth0 add 192.168.122.2 netmask 255.255.255.0
    ifconfig eth0 up

After add this patch, can find the device, and can be used by 'telnetd'
(need cross-build busybox with glibc for it), then outside can telnet to
it without password.
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>