Rename PReadAll/PWriteAll for file descriptor ptr to ReadAll/WriteAll am: 4b28024b7b am: d0e2c2e30d

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/1491176

Change-Id: Ia90fd45216db75d17e6c36f76f735809984fb3fb