l2: skip arp term for locally originated packets

Mark arp packet as locally originated when probing/replying and don't apply any
arp-term logic against it.

Type: fix
Signed-off-by: Stanislav Zaikin <zstaseg@gmail.com>
Change-Id: I305ff5cac8cac456decf92f21b961aa4ce286079
diff --git a/src/vnet/arp/arp_packet.h b/src/vnet/arp/arp_packet.h
index a860c25..66ab384 100644
--- a/src/vnet/arp/arp_packet.h
+++ b/src/vnet/arp/arp_packet.h
@@ -68,6 +68,8 @@
   clib_mem_unaligned (&arp0->ip4_over_ethernet[0].ip4.data_u32, u32) =
     if_addr0->data_u32;
 
+  p0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
+
   /* Hardware must be ethernet-like. */
   ASSERT (vec_len (hw_if0->hw_address) == 6);