checkdeps: remove nix code

[hackbar]

Summary

• What is the goal of this PR? (e.g. Bump up an emulator version, implement a new feature. )
  cleaning up build

Testing

• How was this tested? (e.g. Built and tested on specific devices, manual testing steps, URLs for CI/CD build artifacts.)
• Test results: (e.g. Screenshots, logs, performance metrics if applicable.)
  build locally

Additional Context

• Add any other information that might be helpful for the reviewer (e.g., performance implications, potential risks, specific areas to focus on.)

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AI Usage

While ROCKNIX doesn't have restrictions on AI tools in contributing, please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? NO

[porschemad911]

I believe this is needed for fex-emu, but @tiopex would know best

[tiopex]

yes, this is mandatory for building fex