[foreign-memaccess+abi] RFR: 8274157: java.foreign: Add method MemorySegment::isOverlapping

[Julia Boes]

This change adds a method to the MemorySegment API that detects if two segments are overlapping.

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Commit messages:
 - initial change

Changes: https://git.openjdk.java.net/panama-foreign/pull/585/files
 Webrev: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=585&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274157
  Stats: 176 lines in 4 files changed: 171 ins; 0 del; 5 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/585.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/585/head:pull/585

PR: https://git.openjdk.java.net/panama-foreign/pull/585