RFR: 8343933: Add a MemorySegment::fill benchmark with varying sizes

[Per Minborg]

This PR proposes to add a new `MemorySegment::fill" benchmark where the byte size of the segments varies.

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Commit messages:
 - Use static arrays
 - Revert changes from other branch
 - Add benchmark
 - Add benchmarks

Changes: https://git.openjdk.org/jdk/pull/22010/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22010&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8343933
  Stats: 150 lines in 1 file changed: 150 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/22010.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22010/head:pull/22010

PR: https://git.openjdk.org/jdk/pull/22010