Order of port-creation in a VN with multiple subnets is not predictable

[Vedamurthy Joshi]

Build 1.10 2282 and 1.06 -38 as well.

When VN has multiple subnets, Looks like , the next IP chosen for a new port is chosen from the subnet which was last used using the subnet_id option.
This is unlike stock openstack, where it continues to pick the IP from the first subnet unless specified otherwise (or becomes full)

Create a VN VN1
Create Subnet1 in VN1

neutron port-create VN1 ==> Creates IP in Subnet1

Create Subnet2
neutron port-create VN1 --fixed-ip subnet_id=<Subnet2_id> ==> Creates IP in Subnet2

neutron port-create VN1 ==> Creates IP in Subnet2

neutron port-create VN1 --fixed-ip ip_address=<Subnet1 IP> ==> Creates IP in Subnet1

neutron port-create VN1 ==> Creates IP in Subnet2

Create Subnet3
neutron port-create VN1 --fixed-ip subnet_id=<Subnet3_id> ==> Creates IP in Subnet3

neutron port-create VN1 ==> Creates IP in Subnet3

[Sachin Bansal (sbansal)]

https://github.com/Juniper/contrail-controller/commit/4a4e497b766f9def1803101c0e34dcddf4a1bc35

[Nagabhushana R (bhushana)]

bug was raised before 1.1 branch was cut, the checkin URL points to r1.1, please update with the mainline commit information and move the PR appropriately.