Bump riscv-gnu-toolchain from `f0b0094` to `170a9a3`

Bumps [riscv-gnu-toolchain](https://github.com/riscv/riscv-gnu-toolchain) from `f0b0094` to `170a9a3`.
- [Release notes](https://github.com/riscv/riscv-gnu-toolchain/releases)
- [Commits](https://github.com/riscv/riscv-gnu-toolchain/compare/f0b00941ec640bfdbe31304820892fe9d490f9bb...170a9a3045207e3ed4d396f6c4f03e1c7978b0e4

)

---
updated-dependencies:
- dependency-name: riscv-gnu-toolchain
  dependency-type: direct:production
...

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