[Network] az network nic create fails

[tjprescott]

Tried creating a NIC for a subnet which did not exist.

az network nic create -g vmrg -n nic2 --vnet-name vnet1 --subnet subnet1

'new' is not valid value for enum <enum 'subnetType'>

The help text reads:

Arguments
    --name -n           [Required]: Name of the new NIC.
    --resource-group -g [Required]: Name of resource group.
    --subnet            [Required]: Name or ID of the resource.  Creates new by default.  Use "" for
                                    none.

It is clear from looking at the ARM template that the subnet must be an existing subnet. It looks like an issue with parameter registration.