main, vmm: Remove deprecated --vhost-user-net

This has been superseded by using --net with vhost_user=true and
socket=<socket>

Fixes: #678

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

vmm/src/api/openapi/cloud-hypervisor.yaml

@@ -204,10 +204,6 @@ components:
           type: array
           items:
             $ref: '#/components/schemas/DeviceConfig'
-        vhost_user_net:
-          type: array
-          items:
-            $ref: '#/components/schemas/VhostUserNetConfig'
         vsock:
           type: array
           items:
@@ -405,22 +401,6 @@ components:
           type: boolean
           default: false
 
-    VhostUserNetConfig:
-      required:
-      - sock
-      type: object
-      properties:
-        sock:
-          type: string
-        num_queues:
-          type: integer
-          default: 2
-        queue_size:
-          type: integer
-          default: 256
-        mac:
-          type: string
-
     VsockConfig:
       required:
       - cid