Add IPsec tunnel migration feature flag

This patch adds a feature flag for IPsec tunnel migration. This
implies XFRM_MIGRATE enabled in the kernel.

Bug: 169169973
Test: make
Test: verified on sunfish-eng: added the xml in device.mk,
      built and flashed the phone, the xml showed
      in "adb shell pm list features"
Change-Id: I1d3d6739e0059bbb522b6ce9e3c410ff21089e66
diff --git a/data/etc/android.software.ipsec_tunnel_migration.xml b/data/etc/android.software.ipsec_tunnel_migration.xml
new file mode 100644
index 0000000..c405e1e
--- /dev/null
+++ b/data/etc/android.software.ipsec_tunnel_migration.xml
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2022 The Android Open Source Project
+
+     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.
+-->
+
+<!--
+     This is the feature indicating that the device has support for updating
+     source and destination addresses of IPsec tunnels
+-->
+
+<permissions>
+    <feature name="android.software.ipsec_tunnel_migration" />
+</permissions>