Support RISCV-64

[ziyao233]

This pull request adds support for RISCV-64. WIP now.

[ziyao233]

Now the fork is ok to build on Debian in RISC-V QEMU. Tests are passed.
Additional tests for float/double typed arguments are also added.

[Snaipe]

Can you update the README to add the new architecture support?

It'd be nice if this could be tested automatically; speaking of, it looks like the CI is broken, let me fix it first so that we can test this properly.

[ziyao233]

README.md has been updated :)

[ziyao233]

Any update about the CI?

[romancardenas]

Hey! any news on this? I'm now trying to compile ROS2 for RISC-V and having this package available for RISC-V would make my life way easier :D

[romancardenas]

@ziyao233 please, could you open a PR on https://github.com/ros2/Mimick ? Looks like ROS 2 uses that fork

[ziyao233]

Hey! any news on this? I'm now trying to compile ROS2 for RISC-V and having this package available for RISC-V would make my life way easier :D

The maintainer of this repo does not give me more updates.

if a PR on the fork of ROS2 is helpful, I will do that.