Add missing libffi dependency to LLVM 20.1.8

[Thyre]

(created using eb --new-pr)

See also:

• add libffi as direct dependency in recent LLVM easyconfigs #23429
• {tools}[GCCcore/14.3.0] lit v18.1.8, LLVM v20.1.8, psutil v7.0.0, ... #23459

This was missed while providing LLVM for GCCcore 14.3.0.

[Thyre]

@boegelbot please test @ jsc-zen3

[boegelbot]

@Thyre: Request for testing this PR well received on jsczen3l1.int.jsc-zen3.fz-juelich.de

PR test command 'if [[ develop != 'develop' ]]; then EB_BRANCH=develop ./easybuild_develop.sh 2> /dev/null 1>&2; EB_PREFIX=/home/boegelbot/easybuild/develop source init_env_easybuild_develop.sh; fi; EB_PR=23555 EB_ARGS= EB_CONTAINER= EB_REPO=easybuild-easyconfigs EB_BRANCH=develop /opt/software/slurm/bin/sbatch --job-name test_PR_23555 --ntasks=8 ~/boegelbot/eb_from_pr_upload_jsc-zen3.sh' executed!

• exit code: 0
• output:

Submitted batch job 7450

Test results coming soon (I hope)...

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[boegelbot]

Test report by @boegelbot
SUCCESS
Build succeeded for 1 out of 1 (1 easyconfigs in total)
jsczen3c1.int.jsc-zen3.fz-juelich.de - Linux Rocky Linux 9.6, x86_64, AMD EPYC-Milan Processor (zen3), Python 3.9.21
See https://gist.github.com/boegelbot/693bebdfce44cc82a760e580dda0355f for a full test report.

[Thyre]

@Crivella, can you please take a short look at this? This just aligns the LLVM EasyConfig with the other ones again 😄

[branfosj]

Test report by @branfosj
SUCCESS
Build succeeded for 1 out of 1 (1 easyconfigs in total)
bear-pg0105u03a - Linux RHEL 8.10, x86_64, Intel(R) Xeon(R) Platinum 8360Y CPU @ 2.40GHz (icelake), Python 3.6.8
See https://gist.github.com/branfosj/f566bb27f45dce9b3c13e43ff7459245 for a full test report.

[branfosj]

Going in, thanks @Thyre!