Build java.obex with java_sdk_library

javax.obex is built with java_sdk_library and api files are added by
running "make update-api".
Remove java.obex is from platform.xml, since it will be generated
automatically by soong when the library is built with java_sdk_library.

Bug:77577799
Test: make -j
      make checkapi

Change-Id: Ib94955e62582ffbdfc7eb88cd0e494c61757c7aa
diff --git a/obex/Android.bp b/obex/Android.bp
new file mode 100644
index 0000000..6558eb3
--- /dev/null
+++ b/obex/Android.bp
@@ -0,0 +1,21 @@
+//
+// 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.
+//
+
+java_sdk_library {
+    name: "javax.obex",
+    srcs: ["javax/**/*.java"],
+    api_packages: ["javax.obex"],
+}