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/CleanSpec.mk b/obex/CleanSpec.mk
new file mode 100644
index 0000000..c104234
--- /dev/null
+++ b/obex/CleanSpec.mk
@@ -0,0 +1,18 @@
+#
+# 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.
+#
+
+# runtime lib is renamed from javax.obex.jar to javax.obex.impl.jar
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/framework/javax.obex.jar)