Add obex library source code, build file, and OWNERS file am: 9af11bf90f am: bff9287ebf

Original change: https://android-review.googlesource.com/c/platform/external/obex/+/1995473

Change-Id: Ib2ad1eaa73ccf0a3bdf9e31c3f9828f6b4ddf7d7