RFR: 8338591: Improve performance of MemorySegment::copy

[Per Minborg]

On Fri, 6 Sep 2024 12:05:21 GMT, Per Minborg <pminborg at openjdk.org> wrote:

> Wdyt about the benchmark I have added at [#20829 (comment)](https://github.com/openjdk/jdk/pull/20829#issuecomment-2326404582)?

Added https://bugs.openjdk.org/browse/JDK-8339999

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PR Comment: https://git.openjdk.org/jdk/pull/20829#issuecomment-2346008727