[automerger skipped] Allow tethering pick prefix from all of private address...

[automerger skipped] Allow tethering pick prefix from all of private address range am: c484acc2 -s ours

am skip reason: Change-Id Ib6304eb8b4788e9196d0af48e72f00a6bda73a5f with SHA-1 8a8e7e03 is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/12825260

Change-Id: Ic6adf974d9628e64a5ea41b616df1300d1d9fd0a