RoCEv2 OTG Model

[satyamsinghKey]

Issue: #403

Redocly View:
https://redocly.github.io/redoc/?url=https://raw.githubusercontent.com/open-traffic-generator/models/dev_rocev2/artifacts/openapi.yaml&nocors#tag/Configuration/operation/set_config

Objectives:
Add support of RoCEv2 Protocol in OTG model
Added fields under Configuration and Monitor

Sample Code Snippet:

    config = api.config()
    (device,) = config.devices.device(name="device")

    # device config
    eth = device.ethernets.add()
    eth.name = "eth"
    eth.connection.port_name = port.name
    eth.mac = "00:00:00:00:00:11"
    ipv4 = eth.ipv4_addresses.add()
    ipv4.name = "ipv4"
    ipv4.address = "21.1.1.1"
    ipv4.prefix = 24
    ipv4.gateway = "21.1.1.2"

    rocev2v4 = device.rocev2
    rocev2v4_int = rocev2v4.ipv4_interfaces.add()
    rocev2v4_int.ipv4_name = ipv4.name
    rocev2v4_peer = rocev2v4_int.peers.add()
    rocev2v4_peer.name = "RoCEv2 1"
    rocev2v4_peer.num_of_qps = 2
    rocev2v4_peer.remote_end_point_ip_address = "2.2.2.2"
    rocev2v4_peer.ib_mtu = 15
    flow_settings = rocev2v4_peer.flow_settings.add()
    flow_settings.dscp = 25


    # push configuration
    api.set_config(config)

    # start all protocols
    control_state = api.control_state()
    control_state.protocol.all.state = control_state.protocol.all.START
    api.set_control_state(control_state)

    # create a query for rocev2 metrics
    req = api.metrics_request()
    req.rocev2.peer_names = ["RoCEv2 1"]
    results = api.get_metrics(req)