RFR: 8329545: [s390x] Fix garbage value being passed in Argument Register [v2]

[Sidraya Jayagond]

> Fix sign extension on 4 byte load from argument stack slot to GPR.

Sidraya Jayagond has updated the pull request incrementally with one additional commit since the last revision:

  copyright header

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Changes:
  - all: https://git.openjdk.org/jdk/pull/18601/files
  - new: https://git.openjdk.org/jdk/pull/18601/files/8708acbb..e4e9729d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18601&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18601&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18601.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18601/head:pull/18601

PR: https://git.openjdk.org/jdk/pull/18601