VXLAN: Allow user to specify a custom vxlan tunnel instance id.

If one is not selected by the user, the next available id
will be allocated, thus maintaining backward compatibility.

Change-Id: I4691ed0638b8072f9cfa9f20b9fe4f981e708800
Signed-off-by: Jon Loeliger <jdl@netgate.com>
diff --git a/test/vpp_papi_provider.py b/test/vpp_papi_provider.py
index 242f51c..0e56af1 100644
--- a/test/vpp_papi_provider.py
+++ b/test/vpp_papi_provider.py
@@ -362,7 +362,8 @@
             is_ipv6=0,
             encap_vrf_id=0,
             decap_next_index=0xFFFFFFFF,
-            vni=0):
+            vni=0,
+            instance=0xFFFFFFFF):
         """
 
         :param dst_addr:
@@ -373,6 +374,7 @@
         :param decap_next_index:  (Default value = 0xFFFFFFFF)
         :param mcast_sw_if_index:  (Default value = 0xFFFFFFFF)
         :param vni:  (Default value = 0)
+        :param instance:  (Default value = 0xFFFFFFFF)
 
         """
         return self.api(self.papi.vxlan_add_del_tunnel,
@@ -383,7 +385,8 @@
                          'mcast_sw_if_index': mcast_sw_if_index,
                          'encap_vrf_id': encap_vrf_id,
                          'decap_next_index': decap_next_index,
-                         'vni': vni})
+                         'vni': vni,
+                         'instance': instance})
 
     def geneve_add_del_tunnel(
             self,