FileMap::create: remove duplicate addition. am: 54794ac613 am: 2912d9c190 am: 98e213207f am: a6d7150812 am: 8a192ea12a am: 3c751b9f66

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/12393457

Change-Id: I470769ef78fdfda93b8eee4e8b68065487c2aca1