[jdk21] RFR: 8310459: [BACKOUT] 8304450: [vectorapi] Refactor VectorShuffle implementation

[Tobias Hartmann]

Backport of [JDK-8310459](https://bugs.openjdk.java.net/browse/JDK-8310459). Applies cleanly.

Thanks,
Tobias

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Commit messages:
 - 8310459: [BACKOUT] 8304450: [vectorapi] Refactor VectorShuffle implementation

Changes: https://git.openjdk.org/jdk21/pull/68/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21&pr=68&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8310459
  Stats: 3895 lines in 64 files changed: 1169 ins; 1819 del; 907 mod
  Patch: https://git.openjdk.org/jdk21/pull/68.diff
  Fetch: git fetch https://git.openjdk.org/jdk21.git pull/68/head:pull/68

PR: https://git.openjdk.org/jdk21/pull/68