Bump riscv-opcodes from `5adef50` to `bb64568`

Bumps [riscv-opcodes](https://github.com/riscv/riscv-opcodes) from `5adef50` to `bb64568`.
- [Release notes](https://github.com/riscv/riscv-opcodes/releases)
- [Commits](https://github.com/riscv/riscv-opcodes/compare/5adef50bd3f8aaff379f7f99e5b6817e2dedf0ed...bb64568616b364e7103910f5dd363bc9cad1bb0a

)

---
updated-dependencies:
- dependency-name: riscv-opcodes
  dependency-type: direct:production
...

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