libhevcenc: Update 32 bit chroma neon modules to avoid reading an extra byte am: 42fb245a7b am: 2a3b4e76f9 am: 7fcf5a9629 am: c317c728cf

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/libhevc/+/15163641

Change-Id: I7e4386deabb99adb64f7a81e2c4497d1caa663ef