ipxe: drop unnecessary gnu-efi dependency

Turns out, iPXE doesn't use GNU-EFI but has its own tools for building
EFI PE binaries with a GNU toolchain, and as for headers it has a
vendored-in copy of EFI headers from TianoCore.

pkgs/by-name/gn/gnu-efi/package.nix

@@ -41,7 +41,6 @@ stdenv.mkDerivation (finalAttrs: {
   passthru.tests = {
     inherit
       fwupd-efi
-      ipxe
       syslinux
       ;
   };

pkgs/by-name/ip/ipxe/package.nix

@@ -4,7 +4,6 @@
   fetchFromGitHub,
   unstableGitUpdater,
   buildPackages,
-  gnu-efi,
   mtools,
   openssl,
   perl,
@@ -52,7 +51,6 @@ stdenv.mkDerivation (finalAttrs: {
   version = "1.21.1-unstable-2025-01-10";
 
   nativeBuildInputs = [
-    gnu-efi
     mtools
     openssl
     perl