[jdk21u-dev] RFR: 8343618: Stack smashing in awt_InputMethod.c on Linux s390x

[Zdenek Zambersky]

Backport fixing stack smashing issue in `awt_InputMethod.c` on s390x. Clean.

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Commit messages:
 - Backport ee6891456ed672305d9b48846b5a7977373e1284

Changes: https://git.openjdk.org/jdk21u-dev/pull/1836/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1836&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8343618
  Stats: 20 lines in 1 file changed: 10 ins; 10 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1836.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1836/head:pull/1836

PR: https://git.openjdk.org/jdk21u-dev/pull/1836