RFR: 8336356: [s390x] preserve Vector Register before using for string compress / expand

[Amit Kumar]

This PR adds `TEMP` effect for the vector register, allotted by register allocator, used in the string compress/expand intrinsic. Also it enabled the Vector computation part of those intrinsics which was disabled by https://github.com/openjdk/jdk/pull/18162

-------------

Commit messages:
 - Adds TEMP effect

Changes: https://git.openjdk.org/jdk/pull/22354/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22354&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8336356
  Stats: 214 lines in 3 files changed: 155 ins; 6 del; 53 mod
  Patch: https://git.openjdk.org/jdk/pull/22354.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22354/head:pull/22354

PR: https://git.openjdk.org/jdk/pull/22354