dpdk: add ipsec cryptodev support

DPDK Cryptodev support and related IPsec ESP nodes using DPDK Cryptodev APIs.

When DPDK Cryptodev support is enabled, the node graph is modified by adding
and replacing some of the nodes.

The following nodes are replaced:
* esp-encrypt -> dpdk-esp-encrypt
* esp-decrypt -> dpdk-esp-decrypt

The following nodes are added:
* dpdk-crypto-input : polling input node
* dpdk-esp-encrypt-post : internal node
* dpdk-esp-decrypt-post : internal node

Change-Id: I6dca9a890abaf4fb2a4fffce3fd08ac013e4d701
Signed-off-by: Zhang, Roy Fan <roy.fan.zhang@intel.com>
Signed-off-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
diff --git a/vnet/vnet/devices/dpdk/ipsec/dir.dox b/vnet/vnet/devices/dpdk/ipsec/dir.dox
new file mode 100644
index 0000000..ffebfc4
--- /dev/null
+++ b/vnet/vnet/devices/dpdk/ipsec/dir.dox
@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2016 Intel and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/**
+ @dir vnet/vnet/devices/dpdk/ipsec
+ @brief IPSec ESP encrypt/decrypt using DPDK Cryptodev API
+*/