unixPb: Link libffi.so.4 to libffi.so.6 in SLES12 s390x dockerfile

[Haroon-Khel]

• commit message has one of the standard prefixes
• faq.md updated if appropriate
• other documentation is changed or added (if applicable)
• playbook changes run through VPC or QPC (if you have access)
• VPC/QPC not applicable for this PR
• for inventory.yml changes, bastillion/nagios/jenkins updated accordingly

ref #3026

Needed on sles 12 s390x to avoid this error on smoke tests

15:38:03  Run /home/jenkins/workspace/build-scripts/jobs/jdk8u/jdk8u-linux-s390x-temurin_SmokeTests/openjdkbinary/j2sdk-image/bin/java -version
15:38:03  =JAVA VERSION OUTPUT BEGIN=
15:38:03  Error: dl failure on line 894
15:38:03  Error: failed /home/jenkins/workspace/build-scripts/jobs/jdk8u/jdk8u-linux-s390x-temurin_SmokeTests/openjdkbinary/j2sdk-image/jre/lib/s390x/server/libjvm.so, because libffi.so.6: cannot open shared object file: No such file or directory

After the link is in place, the smoke test passes https://ci.adoptium.net/job/build-scripts/job/jobs/job/jdk8u/job/jdk8u-linux-s390x-temurin_SmokeTests/182/console

[github-actions]

A block has been put on this Pull Request as this repository is temporarily under a code freeze due to an ongoing release cycle.

If this pull request needs to be merged during the release cycle then please comment /merge and a PMC member will be able to remove the block.

If the code freeze is over you can remove this block by commenting /thaw.

[sxa]

Correction: Can you update the commit to have a suitable prefix please

[karianna]

Worth adding a comment as to why?

[Haroon-Khel]

/thaw

[steelhead31]

LGTM

Pull Request unblocked - code freeze is over.