CP-308450 Use the position in new network name_label

Do not use the device name in the new created network name_label
if the device has a position. Given the fact that device names
may be different on different hosts of the pool, even they are of
the same position. So it is more proper to just use the position
in the network name_label.
Also this will be good for interface name change scenario as this
change will not reflect in this default network name_label.

Signed-off-by: Changlei Li <changlei.li@cloud.com>

Author: changlei-li

ocaml/xapi/helpers.ml

@@ -129,11 +129,11 @@ let call_script ?(log_output = Always) ?env ?stdin ?timeout script args =
       raise e
 
 (** Construct a descriptive network name (used as name_label) for a give network interface. *)
-let choose_network_name_for_pif device pos_opt =
-  let pos_str =
-    Option.fold ~none:"" ~some:(Printf.sprintf " (slot %d)") pos_opt
-  in
-  Printf.sprintf "Pool-wide network associated with %s%s" device pos_str
+let choose_network_name_for_pif device = function
+  | Some pos ->
+      Printf.sprintf "Pool-wide network %d" pos
+  | None ->
+      Printf.sprintf "Pool-wide network associated with %s" device
 
 (* !! FIXME - trap proper MISSINGREFERENCE exception when this has been defined *)
 (* !! FIXME(2) - this code could be shared with the CLI? *)