kernel-headers: fix asm symlinks

[dtzWill]

We no longer set "platform", so the code referring to it
did the wrong thing.

Happened to notice that we created an "asm-" symlink.

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

[dezgeg]

Did you notice anything broken? Maybe nothing actually needs this?

[dtzWill]

Haven't noticed anything broken, but without knowing/exploring why this was done originally seemed best to fix it :).

If we're sure it's not useful we can remove this entirely. Maybe it only helps with broken code? Dunno.

[dezgeg]

Well, git shows:

commit 539239d66d55ed7326f5af109d4788a81697b191
Author: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date:   Wed Feb 18 14:53:14 2009 +0000

    * KVM 84.  CIFS/Samba performance still broken.
    * Kernel headers: KVM expects a include/linux/asm-x86 symlink, so
      provide it.
    
    svn path=/nixpkgs/trunk/; revision=14113

include/linux/asm-86 got removed in 2.6.28 almost ten years ago. I doubt anything needs it anymore :)

[dtzWill]

Do we need the other one, asm-x86_64 etc that's created as well? Or we're they both introduced with that commit?

[dezgeg]

Seems to be even older stuff, that directory got removed in Linux 2.6.24. In nixpkgs that seemed to be needed for the out-of-tree (back then) KVM like was mentioned the above commit.

[dtzWill]

Okay so looks like the answer is dropping this fixup entirely! I'll hopefully submit a PR for that soon but feel free if I take too long, got a lot on my plate :3.