This update for xxhash fixes the following issues:

- ship libxxhash0 anf xxhash-devel package to Package Hub 15 SP5. (bsc#1216829)

- Update to release 0.8.2

* ARM NEON speed improvements; on M1 Pro it is +20% speed for
  XXH3 and XXH128 (from 30.0 GB/s to 36 GB/s).
* Added support for ARM's SVE vector extension.
* Resolved some issues with XXH3's s390x vector implementation.