Add kernel info to compatibility.zip

Add kernel configs / version to verified_assembled_vendor_manifest.xml
so that the kernel of the incoming package can be checked against
the framework. Previously, the running kernel was used instead.

Bug: 111125947
Test: test_extract_kernel
Test: manual OTA on Pixel 3 from build:
      Android P (kernel version 4.9.96)
      to ToT build:
      device kernel version = (manually modified) framework requirement = latest,
      PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS = true

Change-Id: Id524a58e94bdb6bba348ca461c9d33614ce451a9

tools/test_extract_kernel.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+#
+# Copyright (C) 2018 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.
+
+import unittest
+from extract_kernel import get_version, dump_version
+
+class ExtractKernelTest(unittest.TestCase):
+  def test_extract_version(self):
+    self.assertEqual("4.9.100", get_version(
+        b'Linux version 4.9.100-a123 (a@a) (a) a\n\x00', 0))
+    self.assertEqual("4.9.123", get_version(
+        b'Linux version 4.9.123 (@) () \n\x00', 0))
+
+  def test_dump_self(self):
+    self.assertEqual("4.9.1", dump_version(
+        b"trash\x00Linux version 4.8.8\x00trash\x00"
+        "other trash Linux version 4.9.1-g3 (2@s) (2) a\n\x00"))