Add loong64 support in seccomp and PIE

[zhaixiaojuan]

I resubmitted a PR to replace #3765

The LoongArch architecture (LoongArch) is an Instruction Set Architecture (ISA) that has a RISC style.
Documentations:
ISA:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html
ABI:
https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html
More docs can be found at:
https://loongson.github.io/LoongArch-Documentation/README-EN.html

[yzewei]

LGTM!

[lifubang]

I'll approve to run the CI, but don’t forget to sign off your commit!

[lifubang]

There are two questions:

1. We might also need to update the documentation regarding the supported architectures:
   https://github.com/zhaixiaojuan/runc/blob/be0377ce139f0a406d3d0f472d5c1b1f7e625053/docs/spec-conformance.md?plain=1#L14
2. Relatedly, have you actually tested this support on a LoongArch64 (loong64) machine?

[AkihiroSuda]

https://github.com/opencontainers/runc/blob/main/docs/spec-conformance.md needs to be updated too