net: Fix bogus "Warning: vlan 0 with no nics" with -device

net_check_clients() prints this when an VLAN has host devices, but no
guest devices.  It uses VLANState members nb_guest_devs and
nb_host_devs to keep track of these devices.  However, -device does
not update nb_guest_devs, only net_init_nic() does that, for -net nic.

Check the VLAN clients directly, and remove the counters.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/net.c b/net.c
index 38b65f4..509f074 100644
--- a/net.c
+++ b/net.c
@@ -812,9 +812,6 @@
     }
 
     nd->used = 1;
-    if (vlan) {
-        nd->vlan->nb_guest_devs++;
-    }
     nb_nics++;
 
     return idx;
@@ -1278,13 +1275,27 @@
 void net_check_clients(void)
 {
     VLANState *vlan;
+    VLANClientState *vc;
+    int has_nic, has_host_dev;
 
     QTAILQ_FOREACH(vlan, &vlans, next) {
-        if (vlan->nb_guest_devs == 0 && vlan->nb_host_devs == 0)
-            continue;
-        if (vlan->nb_guest_devs == 0)
+        QTAILQ_FOREACH(vc, &vlan->clients, next) {
+            switch (vc->info->type) {
+            case NET_CLIENT_TYPE_NIC:
+                has_nic = 1;
+                break;
+            case NET_CLIENT_TYPE_SLIRP:
+            case NET_CLIENT_TYPE_TAP:
+            case NET_CLIENT_TYPE_SOCKET:
+            case NET_CLIENT_TYPE_VDE:
+                has_host_dev = 1;
+                break;
+            default: ;
+            }
+        }
+        if (has_host_dev && !has_nic)
             fprintf(stderr, "Warning: vlan %d with no nics\n", vlan->id);
-        if (vlan->nb_host_devs == 0)
+        if (has_nic && !has_host_dev)
             fprintf(stderr,
                     "Warning: vlan %d is not connected to host network\n",
                     vlan->id);