ARP: don't use RPC for requests initiated from the main thread

Change-Id: If833680149eb33db6adc836c5330f350042869f4
Signed-off-by: Neale Ranns <nranns@cisco.com>
diff --git a/src/vnet/ethernet/arp.h b/src/vnet/ethernet/arp.h
index 7b50ed7..6c89d1e 100644
--- a/src/vnet/ethernet/arp.h
+++ b/src/vnet/ethernet/arp.h
@@ -26,12 +26,16 @@
 
 extern int vnet_arp_set_ip4_over_ethernet (vnet_main_t * vnm,
 					   u32 sw_if_index,
-					   void *a_arg,
-					   int is_static,
+					   const
+					   ethernet_arp_ip4_over_ethernet_address_t
+					   * a, int is_static,
 					   int is_no_fib_entry);
 
 extern int vnet_arp_unset_ip4_over_ethernet (vnet_main_t * vnm,
-					     u32 sw_if_index, void *a_arg);
+					     u32 sw_if_index,
+					     const
+					     ethernet_arp_ip4_over_ethernet_address_t
+					     * a);
 
 extern int vnet_proxy_arp_fib_reset (u32 fib_id);