guestfs: add OVMF package for UEFI firmware support

The OVMF (Open Virtual Machine Firmware) package provides UEFI firmware
files required by libvirt when creating VMs with UEFI support. Without
this package, libvirt fails with:

  libvirtError: operation failed: Unable to find 'efi' firmware that
  is compatible with the current configuration

Add ovmf to the Debian dependencies to ensure UEFI firmware is available
for VM creation, particularly when guestfs_requires_uefi is enabled.

Generated-by: Claude AI
Reviewed-by: Chuck Lever <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

Author: mcgrof

playbooks/roles/guestfs/tasks/install-deps/debian/main.yml

@@ -17,4 +17,5 @@
       - isc-dhcp-client
       - python3-lxml
       - python3-libvirt
+      - ovmf
     state: present