[Dependabot]: Bump neorv32 from 549b0b9 to 12715a3

Bumps [neorv32](https://github.com/stnolting/neorv32) from `549b0b9` to `12715a3`.
- [Release notes](https://github.com/stnolting/neorv32/releases)
- [Commits](stnolting/neorv32@549b0b9...12715a3)

---
updated-dependencies:
- dependency-name: neorv32
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>