ROCm 6.4 does not yet publish a Release file for Debian Bookworm, causing
the live-build chroot hook to fail with "does not have a Release file".
Try each version in ROCM_CANDIDATES order; skip to the next if apt-get update
fails (repo unavailable). Exit gracefully if none are available.
Also rename inner 'candidate' variable to 'smi_path' to avoid collision.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
58510207fa