[Testbed] Support config extra mgmt IP on PTF

[lizhijianrd]

Description of PR

Summary:
Support config extra MGMT IP addresses on PTF while add-topo. The extra IPs are used for non-routable traffic inside testbed.

How to use this feature
To configure multi MGMT IP addresses on PTF, update the testbed.yaml and add your extra MGMT addresses in the key ptf_extra_mgmt_ip. For example:

- conf-name: vms-sn2700-t1
  group-name: vms1-1
  topo: t1
  ptf_image_name: docker-ptf
  ptf: ptf-unknown
  ptf_ip: 10.255.0.178/23
  ptf_ipv6:
  ptf_extra_mgmt_ip: ["172.16.188.178/17", "172.16.188.179/17"]
  server: server_1
  vm_base: VM0100
  dut:
    - str-msn2700-01
  inv_name: lab
  auto_recover: 'True'
  comment: Tests Mellanox SN2700 vms

After add-topo, we can find 3 IP addresses configured on the mgmt port:

root@bafc741834e8:~# ip addr show mgmt
23843: mgmt@if23844: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 5a:be:4d:b5:4e:04 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 10.255.0.178/23 scope global mgmt
       valid_lft forever preferred_lft forever
    inet 172.16.188.178/17 scope global mgmt
       valid_lft forever preferred_lft forever
    inet 172.16.188.179/17 scope global secondary mgmt
       valid_lft forever preferred_lft forever

To keep backward compatibility, key ptf_extra_mgmt_ip is not required.

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• Test case(new/improvement)

Back port request

• 201911
• 202012
• 202205

Approach

What is the motivation for this PR?

Support config extra MGMT IP addresses on PTF while add-topo.

How did you do it?

Updated add-topo related ansible playbooks and testbed-cli.sh to support this feature.

How did you verify/test it?

Verified on below situations:

• Testbed without key ptf_extra_mgmt_ip.
• Testbed with ptf_extra_mgmt_ip: [].
• Testbed with ptf_extra_mgmt_ip: [<a-single-extra-ip>].
• Testbed with ptf_extra_mgmt_ip: [<extra-ip-1>, <extra-ip-2>].

Any platform specific information?

Supported testbed topology if it's a new test case?

Documentation