net/mlx5: E-Switch, Read PF mac address

External controller PF's MAC address is not read from the device during
vport setup. Fail to read this results in showing all zeros to user
while the factory programmed MAC is a valid value.

$ devlink port show eth1 -jp
{
    "port": {
        "pci/0000:03:00.0/196608": {
            "type": "eth",
            "netdev": "eth1",
            "flavour": "pcipf",
            "controller": 1,
            "pfnum": 0,
            "splittable": false,
            "function": {
                "hw_addr": "00:00:00:00:00:00"
            }
        }
    }
}

Hence, read it when enabling a vport.

After the fix,

$ devlink port show eth1 -jp
{
    "port": {
        "pci/0000:03:00.0/196608": {
            "type": "eth",
            "netdev": "eth1",
            "flavour": "pcipf",
            "controller": 1,
            "pfnum": 0,
            "splittable": false,
            "function": {
                "hw_addr": "98:03:9b:a0:60:11"
            }
        }
    }
}

Fixes: f099fde1

 ("net/mlx5: E-switch, Support querying port function mac address")
Signed-off-by: Bodong Wang <bodong@nvidia.com>
Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Alaa Hleihel <alaa@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>