[jdk17u-dev] RFR: 8273380: ARM32: Default to {ldrexd,strexd} in StubRoutines::atomic_{load|store}_long

[Aleksey Shipilev]

Clean backport to make ARM32 safer.

Additional testing:
 - [x] Linux ARM32 cross-builds
 - [ ] Linux ARM32 `make bootcycle-images`

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Commit messages:
 - Backport 718eff2bb6e938440df9f7b982ef6d2f4060a759

Changes: https://git.openjdk.org/jdk17u-dev/pull/909/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=909&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8273380
  Stats: 20 lines in 1 file changed: 8 ins; 8 del; 4 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/909.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/909/head:pull/909

PR: https://git.openjdk.org/jdk17u-dev/pull/909