RFR: 8321542: C2: Missing ChaCha20 stub for x86_32 leads to crashes [v2]

[Jamil Nimeh]

> This fix corrects an oversight in the ChaCha20 intrinsics delivered by JDK-8247645.  An ifdef guard is now part of the x86 ChaCha20 intrinsics code which disables them by default on 32-bit platforms, as this architecture was not part of the feature delivery.

Jamil Nimeh has updated the pull request incrementally with one additional commit since the last revision:

  Modify warning message on 32-bit

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Changes:
  - all: https://git.openjdk.org/jdk/pull/17072/files
  - new: https://git.openjdk.org/jdk/pull/17072/files/fe0d4461..ff55249e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=17072&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=17072&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/17072.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17072/head:pull/17072

PR: https://git.openjdk.org/jdk/pull/17072