monitor: Add netdev_add type argument completion.

Also update the command's documentation.

Signed-off-by: Hani Benhabiles <hani@linux.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
diff --git a/hmp-commands.hx b/hmp-commands.hx
index 3e7b29c..a7f9b2f 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1234,9 +1234,10 @@
     {
         .name       = "netdev_add",
         .args_type  = "netdev:O",
-        .params     = "[user|tap|socket|hubport|netmap],id=str[,prop=value][,...]",
+        .params     = "[user|tap|socket|vde|bridge|hubport|netmap],id=str[,prop=value][,...]",
         .help       = "add host network device",
         .mhandler.cmd = hmp_netdev_add,
+        .command_completion = netdev_add_completion,
     },
 
 STEXI