ipsec: Default the IPSec interface MTU to 9000

Type: fix

The same value is used for other tunnel types.

Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: I6593001918993d65f127cc9f716c95e932239842
diff --git a/src/vnet/ipsec/ipsec_itf.c b/src/vnet/ipsec/ipsec_itf.c
index 5f04fcf..ae8e342 100644
--- a/src/vnet/ipsec/ipsec_itf.c
+++ b/src/vnet/ipsec/ipsec_itf.c
@@ -305,6 +305,7 @@
 					 t_idx);
 
   hi = vnet_get_hw_interface (vnm, hw_if_index);
+  vnet_sw_interface_set_mtu (vnm, hi->sw_if_index, 9000);
 
   vec_validate_init_empty (ipsec_itf_index_by_sw_if_index, hi->sw_if_index,
 			   INDEX_INVALID);