RFR: 8340307: Add explanation around MemorySegment:reinterpret regarding arenas [v6]

[Per Minborg]

> This PR proposes to add a small text segment on the `MemorySegment::reinterpret` overloads that takes an Arena stating the responsibility of actually freeing reinterpreted segments lies with the *original* arena.

Per Minborg has updated the pull request incrementally with one additional commit since the last revision:

  Update src/java.base/share/classes/java/lang/foreign/MemorySegment.java
  
  Co-authored-by: Jorn Vernee <JornVernee at users.noreply.github.com>

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Changes:
  - all: https://git.openjdk.org/jdk/pull/21761/files
  - new: https://git.openjdk.org/jdk/pull/21761/files/771804be..838f5138

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21761&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21761&range=04-05

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21761.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21761/head:pull/21761

PR: https://git.openjdk.org/jdk/pull/21761