✨ Add ARM suport to VM template

[honza]

A few improvements in the multi-arch space:

• Add an architecture field to flavors (defaults to libvirt arch)
• Allow consumers to provide their own template for setting up VMs
• Add some changes to allow us to boot an arm VM (largely provided by Claude)

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[Copilot]

Pull request overview

This PR adds ARM (aarch64) architecture support to the VM template system, enabling multi-architecture deployments. The changes introduce a new architecture field to VM flavors and allow cross-architecture VM emulation.

Key changes:

• Add architecture field to flavors (defaults to libvirt_arch)
• Implement ARM-specific VM configuration including EFI firmware, CPU model, and video driver
• Enable custom VM template override via baremetal_vm_template variable

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
vm-setup/roles/libvirt/templates/baremetalvm.xml.j2	Adds ARM-specific VM configuration with conditional logic for OS setup, CPU model, and device settings based on flavor architecture
vm-setup/roles/libvirt/tasks/vm_setup_tasks.yml	Allows consumers to specify a custom VM template via baremetal_vm_template variable
vm-setup/roles/common/templates/ironic_nodes.json.j2	Updates Ironic node properties to use flavor-specific architecture instead of global libvirt_arch
vm-setup/roles/common/defaults/main.yml	Adds architecture field to default flavor configuration with libvirt_arch as the default value

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[kashifest]

Overall lgtm

[Rozzii]

Thanks for this contribution.
Generally looks fine but I am a bit confused related to EFI+ARM.
I have commented the at the relevant section.

[Rozzii]

AFAIK EFI + ARM are not a mandatory combination like on x86, many ARM systems and RISC systems (actually all that I have worked with) have no EFI firmware or ACPI or anything akin to the "BIOS/UEFI" that folks are used to on x86/amd64 motherboards.

That said I never emulated arm on libvirt so I am not familiar with how this section should look like, but I would suggest separating is_arm from is_arm_efi or something like that.

[honza]

Claude came up with checking libvirt_firmware, what do you think?