emacs30: add a patch to fix upstream bug 67916

[jian-lin]

https://debbugs.gnu.org/cgi/bugreport.cgi?bug=67916

Bug: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=67916

Inhibit lexical cookie warning for *-pkg.el files (bug#67916)

Users may use byte-compile-error-on-warn to turn compilation warnings
into errors to make sure their Emacs lisp packages are warning-free.
Emacs bug 67916 makes that difficult because the Emacs-generated file
*-pkg.el emits a compilation warning about missing lexical cookie.

There is an upstream patch to fix this. That patch makes Emacs also
generate the needed lexical cookie when generating *-pkg.el files.
However, that patch has stalled.

This patch takes an easier but less accurate approach by inhibiting
lexical cookie warning for *-pkg.el files. Given that not all
*-pkg.el files are generated by Emacs, to reduce impact, this patch
also checks no-byte-compile.

---

This patch can be verified by building a simple elisp package foo.el with turnCompilationWarningToError enabled:

;;; foo.el --- A test file  -*- lexical-binding: t; -*-

;; Version: 1.0.0

(provide 'foo)

;;; foo.el ends here

$ nix build -Lv --include nixpkgs=$PWD --impure --expr 'with (import <nixpkgs> { config = { }; overlays = [ ]; }); emacs30.pkgs.elpaBuild { pname = "foo"; version = "1.0.0"; turnCompilationWarningToError = true; src = writeText "foo.el" ";;; foo.el --- A test file  -*- lexical-binding: t; -*-\n;; Version: 1.0.0\n(provide \'foo)\n;;; foo.el ends here"; }'

Previously, the build failed. With this patch applied, the build succeeds.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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