RFR: 8346609: Improve MemorySegment.toString

[Per Minborg]

This PR proposes to improve the current `MemorySegment.toString()` method from:

`MemorySegment{ address: 0x60000264c540, byteSize: 8 }`

to

`MemorySegment{ native, address: 0x60000264c540, byteSize: 8, confined, not alive, read-only, mapped }`

Tests passes tier1-tier3

-------------

Commit messages:
 - Implement an alternate MS::toString
 - Improve MemorySegment::toString

Changes: https://git.openjdk.org/jdk/pull/22826/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22826&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346609
  Stats: 30 lines in 3 files changed: 28 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/22826.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22826/head:pull/22826

PR: https://git.openjdk.org/jdk/pull/22826