RFR: 8343933: Add a MemorySegment::fill benchmark with varying sizes [v2]

[Per Minborg]

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

Per Minborg has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains six additional commits since the last revision:

 - Add mixed test
 - Merge branch 'master' into ms-fill-bench-sizes
 - Use static arrays
 - Revert changes from other branch
 - Add benchmark
 - Add benchmarks

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Changes:
  - all: https://git.openjdk.org/jdk/pull/22010/files
  - new: https://git.openjdk.org/jdk/pull/22010/files/8760cc87..7734ee3b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22010&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22010&range=00-01

  Stats: 12724 lines in 321 files changed: 9622 ins; 1868 del; 1234 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