[automerger skipped] cleanup - read_config() and ipv4_local_prefixlen am: 8452f3f652 -s ours

am skip reason: Change-Id I67b70fe298f69ac51dfbc5daf4078b842fb62808 with SHA-1 ba667df1c1 is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/android-clat/+/11736257

Change-Id: I95fa00a1ee12dfc084e3f0ef79b1684e5597ef2a