Passing profiles in argv breaks on lots of generations

[grahamc]

Here is a small sample:

+ /nix/store/y8cginvrvarrm1x1axvivynv3rnajvqp-bootspec-unreleased/bin/generator /nix/var/nix/profiles/system-10-link /nix/var/nix/profiles/system-11-link /nix/var/nix/profiles/system-12-link /nix/var/nix/profiles/system-13-link /nix/var/nix/profiles/system-14-link /nix/var/nix/profiles/system-15-link /nix/var/nix/profiles/system-16-link /nix/var/nix/profiles/system-17-link /nix/var/nix/profiles/system-18-link /nix/var/nix/profiles/system-19-link /nix/var/nix/profiles/system-1-link /nix/var/nix/profiles/system-20-link /nix/var/nix/profiles/system-21-link /nix/var/nix/profiles/system-22-link /nix/var/nix/profiles/system-23-link /nix/var/nix/profiles/system-24-link /nix/var/nix/profiles/system-25-link /nix/var/nix/profiles/system-26-link /nix/var/nix/profiles/system-27-link /nix/var/nix/profiles/system-28-link /nix/var/nix/profiles/system-29-link /nix/var/nix/profiles/system-2-link /nix/var/nix/profiles/system-30-link /nix/var/nix/profiles/system-31-link /nix/var/nix/profiles/system-32-link /nix/var/nix/profiles/system-33-link /nix/var/nix/profiles/system-34-link /nix/var/nix/profiles/system-35-link /nix/var/nix/profiles/system-36-link /nix/var/nix/profiles/system-37-link /nix/var/nix/profiles/system-38-link /nix/var/nix/profiles/system-39-link /nix/var/nix/profiles/system-3-link /nix/var/nix/profiles/system-40-link /nix/var/nix/profiles/system-41-link /nix/var/nix/profiles/system-42-link /nix/var/nix/profiles/system-43-link /nix/var/nix/profiles/system-44-link /nix/var/nix/profiles/system-45-link /nix/var/nix/profiles/system-46-link /nix/var/nix/profiles/system-47-link /nix/var/nix/profiles/system-48-link /nix/var/nix/profiles/system-49-link /nix/var/nix/profiles/system-4-link /nix/var/nix/profiles/system-50-link /nix/var/nix/profiles/system-51-link /nix/var/nix/profiles/system-52-link /nix/var/nix/profiles/system-53-link /nix/var/nix/profiles/system-54-link /nix/var/nix/profiles/system-55-link /nix/var/nix/profiles/system-56-link /nix/var/nix/profiles/system-57-link /nix/var/nix/profiles/system-5-link /nix/var/nix/profiles/system-6-link /nix/var/nix/profiles/system-7-link /nix/var/nix/profiles/system-8-link /nix/var/nix/profiles/system-9-link --systemd-machine-id-setup /nix/store/q0881awy50g4srnnwasci37y2jk5sf99-systemd-249.5/bin/systemd-machine-id-setup --unified-efi --objcopy /nix/store/js66s0xwjnzg0ggi2lq9bcvlk6x2za13-binutils-2.35.2/bin/objcopy --systemd-efi-stub /nix/store/q0881awy50g4srnnwasci37y2jk5sf99-systemd-249.5/lib/systemd/boot/efi/linuxx64.efi.stub

and this is just ~50. These should probably be passed as a file.