Bump riscv-opcodes from `3ca60c5` to `2c457dd`

Bumps [riscv-opcodes](https://github.com/riscv/riscv-opcodes) from `3ca60c5` to `2c457dd`.
- [Commits](https://github.com/riscv/riscv-opcodes/compare/3ca60c50f8ea1ea514bcfff58719f670194c1dc8...2c457dd5471195c16c72981a2c8fc7b4c8564794

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

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