RFR: 8278411: Implement UseHeavyMonitors consistently, s390 port [v2]

[Amit Kumar]

> This PR make s390x to adapt the changes done in [JDK-8276901](https://bugs.openjdk.org/browse/JDK-8276901) OR implements UseHeavyMonitors. 
> 
> [JDK-8291555](https://bugs.openjdk.org/browse/JDK-8291555) still needs Porting effort. As for `LM_LIGHTWEIGHT` locking mode, code is Unimplemented.

Amit Kumar has updated the pull request incrementally with one additional commit since the last revision:

  suggestion from @TheRealMDoerr and @tstuefe

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/13978/files
  - new: https://git.openjdk.org/jdk/pull/13978/files/f5af1367..c06afdb9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13978&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13978&range=00-01

  Stats: 4 lines in 2 files changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/13978.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13978/head:pull/13978

PR: https://git.openjdk.org/jdk/pull/13978