RFR: 8359114: [s390x] Add z17 detection code [v2]

[Manjunath S Matti.]

> Add support to detect the new generation of Z machine (z17).

Manjunath S Matti. has updated the pull request incrementally with one additional commit since the last revision:

  Correct the comments for the bits covered in DW[2] and DW[3].

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Changes:
  - all: https://git.openjdk.org/jdk/pull/25718/files
  - new: https://git.openjdk.org/jdk/pull/25718/files/c4a81e7b..95c2fa9e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25718&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25718&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/25718.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25718/head:pull/25718

PR: https://git.openjdk.org/jdk/pull/25718