Enable xoroshiro assembly routine

Describe the bug

Enable the xoroshiro assembly routine in xoroshiro-gen instead of using the VOP.

In !202 (merged), and assembly routine for updating the xoroshiro generator is implemented. However, as mentioned there, we can't actually use it. It causes compilation errors which aren't fixed by doing a cross-compile.

The easiest approach is to land !202 (merged) and create a snapshot that we can use for CI. Once that is in place, we can then use that to enable the assembly routine and also remove the old VOP. Once this is in place, we can then actually create an official snapshot.