vCenter: Fix ContrailVM interface names

- Fix involves - not executing /firstboot at ContrailVM creation,
  this will result in the following names for the ContrailVM

                mgmt      ctrl-data    vmware_physical_intf

single-intf     ens160    --           ens192

multi-intf      ens160    ens192       ens224
(ctrl-data)

multi-intf      ens160    ens192       ens224
(pci/sriov)

  This change is done and saved in the ContrailVM vmdk.

- When finding vmware_physical_interface, exclude PCI/SRIOV
  interfaces (driver_type should be vmxnet3)

Change-Id: Iffed0cd9125cd98e5b232ce30428f3ece6a19986
Closes-Bug: #1781121

containers/vrouter/base/agent-functions.sh

@@ -181,9 +181,10 @@ function get_physical_nic_and_mac()
 }
 
 # Find the overlay interface on a ContrailVM
-# ContrailVM is spawned with nic ens160, which is the primary interface
+# ContrailVM is spawned with nic ens160, which is the primary/mgmt interface
 # Secondary nics (like ens192, ens224) are added during provisioning
-# The overlay interface will have name ens* and not have inet* configured
+# The overlay interface will have name ens*, be of type vmxnet3
+# and not  have inet address configured
 # This function uses this logic to find the overlay interface and
 # return as vmware_physical_interface.
 function get_vmware_physical_iface() {
@@ -192,11 +193,16 @@ function get_vmware_physical_iface() {
     local iface_list=`ip -o link show | awk -F': ' '{print $2}'`
     iface_list=`echo "$iface_list" | grep ens`
     for iface in $iface_list; do
-        ip addr show dev $iface | grep 'inet ' > /dev/null 2>&1
-        if [[ $? == 0 ]]; then
-            continue;
+        local intf_type=`ethtool -i $iface | grep driver | cut -f 2 -d ' '`
+        if [[ $intf_type != "vmxnet3" ]]; then
+             continue;
         else
-            vmware_int=$iface
+             ip addr show dev $iface | grep 'inet ' > /dev/null 2>&1
+             if [[ $? == 0 ]]; then
+                  continue;
+             else
+                  vmware_int=$iface
+             fi
         fi
     done
     if [[ "$vmware_int" == '' ]]; then