Add riscv64 ci node for JustJ

Summary

Like the Platform's #4978 (closed) issue, I'd like to build riscv64 JREs for JustJ.

For that I need an additional agent/node here:

https://ci.eclipse.org/justj/computer/

Do I I really need yet another resource resource pack? I should note that such an agent is used 3 or 4 time every few months. I imagine the platform would be happy to share their agent when they have one given they will be making using the JustJ JRE for risc64.

Priority

• Urgent
• High
• Medium
• Low

Severity

• Blocker
• Major
• Normal
• Low

Impact

I cannot produce JREs for Linux riscv64 which will be one of the platform's supported architectures and it will be useful for improving and simplifying SWT's native builds.