RFR: 8263260: [s390] Support latest hardware (z14 and z15) [v2]

[Lutz Schmidt]

> 8263260: [s390] Support latest hardware (z14 and z15)

Lutz Schmidt has updated the pull request incrementally with one additional commit since the last revision:

  Changes as requested by TheRealMDoerr

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2918/files
  - new: https://git.openjdk.java.net/jdk/pull/2918/files/c8dcfb44..1ab0d054

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2918&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2918&range=00-01

  Stats: 58 lines in 2 files changed: 24 ins; 16 del; 18 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2918.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2918/head:pull/2918

PR: https://git.openjdk.java.net/jdk/pull/2918