RFR: 8284990: AArch64: Remove STXR_PREFETCH from CPU features

Tue Jul 26 15:09:08 UTC 2022

As STXR_PREFETCH is usually done unconditionally in non-JVM code, e.g.,
Linux ARM Kernel[1], this patch removes VM_Version::CPU_STXR_PREFETCH
and generates it unconditionally.

[1] https://patchwork.kernel.org/project/linux-arm-kernel/patch/1436779519-2232-16-git-send-email-will.deacon@arm.com/

[TEST]
Full Jtreg passed without new failure.

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Commit messages:
 - 8284990: AArch64: Remove STXR_PREFETCH from CPU features

Changes: https://git.openjdk.org/jdk/pull/9641/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9641&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8284990
  Stats: 18 lines in 5 files changed: 0 ins; 11 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/9641.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9641/head:pull/9641

PR: https://git.openjdk.org/jdk/pull/9641