[jdk17u-dev] RFR: 8267860: Off-by-one bug when searching arrays in AlpnGreaseTest

[Martin Doerr]

Backport of [JDK-8267860](https://bugs.openjdk.org/browse/JDK-8267860).

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Commit messages:
 - Backport 2adef6a1f84d478bb38b179795f08ffa43680e36

Changes: https://git.openjdk.org/jdk17u-dev/pull/1644/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1644&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8267860
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1644.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1644/head:pull/1644

PR: https://git.openjdk.org/jdk17u-dev/pull/1644