scudo: Make prepareTaggedChunk() and resizeTaggedChunk() generic. am: 34c8857fef am: e29ac9f814 am: a918bc257a

Original change: https://android-review.googlesource.com/c/platform/external/scudo/+/1683948

Change-Id: I838db314899b4e45c02733747c81610dfedde169