fix(test): give each filesystem profile its own OVMF NVRAM file

init_vm_paths suffixed the disk image per profile but shared one
OVMF_VARS.fd across btrfs and zfs. NVRAM holds the UEFI boot entries and
lives outside the qcow2, so a disk-snapshot revert can't restore it. A zfs
run's ZFSBootMenu entries clobbered the btrfs GRUB entry, and with no
removable ESP fallback the btrfs base then booted to "no bootable device"
and timed out before archsetup ran.

NVRAM now carries the same per-profile suffix as the disk image, so the two
profiles keep separate boot state. Validated by a full green zfs run
(ArchSetup exit 0, Testinfra 96 passed / 0 failed).

0 files changed, 0 insertions, 0 deletions