nixos/azure: add Gen 2 VM, aarch64 and accelerated networking support

[codgician]

Description of changes

[azure-agent]

• Removed x86 assertion as the latest waagent already works on aarch64.

[azure-common]

• Added option to enable support for accelerated networking, following official doc for custom vm image: virtualisation.azure.acceleratedNetworking = true.
• Remove reference of headless profile to make the console input work (and being able to select boot entries).

[azure-image]

• Added option for generating Gen 2 VM image (efi partition): virtualisation.azureImage = "v1" or "v2".
• Added option for specifying esp partition size: virtualisation.azureImage.bootSize

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I have created an example flake for generating a test vhd for this change: github:codgician/azure-aarch64-nixos.

The result is promising:

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/)
• 24.11 Release Notes (or backporting 23.11 and 24.05 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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[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-ready-for-review/3032/4451

[zimbatm]

thanks for your work!

Given the modules haven't been touched since 2016, I propose to merge your work once you confirm that everything is working as intended.

[zimbatm]

Assuming that the 👍 means it's all good