Tidy .mk files

Add missing headers.
Remove unnecessary lines.

Test: build only
Change-Id: I2d46b9f739b83f16cced2cde34828ea2190a21d7
diff --git a/output_data/Android.mk b/output_data/Android.mk
index 888404c..1711bfd 100644
--- a/output_data/Android.mk
+++ b/output_data/Android.mk
@@ -1,3 +1,18 @@
+# -*- mode: makefile -*-
+# 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.
+
 LOCAL_PATH := $(call my-dir)
 
 include $(call all-makefiles-under,$(LOCAL_PATH))