meta-evb: meta-evb-arm: Enable Second ethernet controller as Redfish HI

* Enable Virtio-net as Redfish HI (eth0) and SMSC_91C111 as BMC Nic (eth1)
* Configure static IP address of virtio-net (eth0)

Using TAP Interface that allows multiple FVP instances can reach out each
other. For example, HOST (RDV3R1) can reach out Redfish service (BMC) via
IP address 192.168.122.10

root@fvp:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 72:45:77:AA:F7:88
          inet addr:192.168.122.10  Bcast:192.168.122.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:273 errors:0 dropped:236 overruns:0 frame:0
          TX packets:50 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:16221 (15.8 KiB)  TX bytes:7214 (7.0 KiB)

eth1      Link encap:Ethernet  HWaddr 00:02:F7:EF:40:EF
          inet addr:172.20.51.1  Bcast:172.20.51.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:34 errors:0 dropped:0 overruns:0 frame:0
          TX packets:48 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4777 (4.6 KiB)  TX bytes:12523 (12.2 KiB)
          Interrupt:19 Base address:0x1000 DMA chan:ff

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:13 errors:0 dropped:0 overruns:0 frame:0
          TX packets:13 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1655 (1.6 KiB)  TX bytes:1655 (1.6 KiB)

Signed-off-by: John Chung <john.chung@arm.com>
Change-Id: I13e4003026d1b145971dd6781df97f2fe2d70b85