Add certificate utils to keystore2 crypto

This patch adds code for certificate generation with boringssl.
This is required for the Keymaster to KeyMint legacy wrapper.

Bug: 171351607
Test: keystore2_crypto_test
Change-Id: Id2d35be04cb5ab8c4e6b0597f5a970150ab9e69b
diff --git a/keystore2/src/tests/gtest_main.cpp b/keystore2/src/tests/gtest_main.cpp
new file mode 100644
index 0000000..149cbbc
--- /dev/null
+++ b/keystore2/src/tests/gtest_main.cpp
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#include <gtest/gtest.h>
+int main(int argc, char** argv) {
+    ::testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}