AIDEGen: Add aidegen as a build target.

For aidegen prebuilt binary release process.

Bug: 119642842
Test: m aidegen;$ANDROID_HOST_OUT/bin/aidegen tradefed
Change-Id: I247ceb8ac116c033f808de6af2d60618644aa8fe
diff --git a/aidegen/Android.mk b/aidegen/Android.mk
new file mode 100644
index 0000000..44f5996
--- /dev/null
+++ b/aidegen/Android.mk
@@ -0,0 +1,15 @@
+# Copyright 2018 - The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+$(call dist-for-goals,droidcore,$(HOST_OUT_EXECUTABLES)/aidegen)