net: use qemu_send_packet_raw() in qemu_announce_self()

Use qemu_send_packet_raw to send gratuitous arp. This will ensure that
vnet header is handled properly.

Also, avoid sending the gratuitous packet to the guest. There doesn't
appear to be any reason for doing that and the code will currently just
crash if the NIC is not associated with a vlan.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

savevm.c

@@ -126,8 +126,6 @@ static int announce_self_create(uint8_t *buf,
 static void qemu_announce_self_once(void *opaque)
 {
     int i, len;
-    VLANState *vlan;
-    VLANClientState *vc;
     uint8_t buf[60];
     static int count = SELF_ANNOUNCE_ROUNDS;
     QEMUTimer *timer = *(QEMUTimer **)opaque;
@@ -136,10 +134,7 @@ static void qemu_announce_self_once(void *opaque)
         if (!nd_table[i].used)
             continue;
         len = announce_self_create(buf, nd_table[i].macaddr);
-        vlan = nd_table[i].vlan;
-        QTAILQ_FOREACH(vc, &vlan->clients, next) {
-            vc->receive(vc, buf, len);
-        }
+        qemu_send_packet_raw(nd_table[i].vc, buf, len);
     }
     if (--count) {
         /* delay 50ms, 150ms, 250ms, ... */