Interface link training and adv_speed configuration.

[kamalkrbh]

• [x] Configurable link training.
• [x] Configurable adv_speed.
• [x] Autoneg and port speed which is already configurable the path and payload can be modified as listed below to make it single with other ethernet params.
• [x] DB Update - via gNMI subscriptions, The respective gNMI path is already subscribed in gnmi_sub.py
• [x] Test case for validating config changes/addition.
• [x] Respective changes on UI.

SONiC Player cell in interface.ipynb - "SET Ethernet Properties - Speed,FEC,Auto-Negotiate,Standalone Link Training"

{
    "openconfig-if-ethernet:config": {
        "advertised-speed": "",
        "auto-negotiate": False,
        "port-fec": "FEC_DISABLED",
        "port-speed": "SPEED_10GB",
        "standalone-link-training": False,
    }
}

openconfig-interfaces:interfaces/interface={interface_name}/openconfig-if-ethernet:ethernet/config