missing sysusr-usr.mount depenency for /usr mounted from ZFS during systemd-boot

[nazarewk]

Describe the bug

fstab-generator generates sysusr-usr.mount for mounting since 2021, but for some reason it's not properly registered in zfs-import-<pool> resulting in sysusr-usr.mount failing in one of the first steps of the initdr boot process.

Steps To Reproduce

Didn't try replicating it anywhere else and I'm not sure why it doesn't fail on zfs legacy mounts as opposed to mounting through zfs

Expected behavior

I expect system to boot properly

Screenshots

If applicable, add screenshots to help explain your problem.

Additional context

My setup is:

1. systemd-boot
2. ZFS root on top of LUKS volume
3. the failing computer uses zfs mountpoints instead of legacy
   • the one I'm writing from has legacy mounts nad works fine

After yesterday's update (roughly 1-2 weeks since previous nixpkgs-unstable update) I'm getting sysusr-usr.mount failure before LUKS gets decrypted and it drops into emergency shell after decrypting volume.
In an emergency shell I can just systemctl start sysusr-usr.mount followed by exit and it boots properly.

Might be related/the same issue, but previously (nixpkgs-unstable from between 2week ago to month ago) I was often getting random boot process hangups: it was pending for some unit I couldn't see without failing/dropping into emergency shell.

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Metadata

kdn@oams ~> nix-shell -p nix-info --run "nix-info -m"
nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 6.1.54-rt15, NixOS, 23.11 (Tapir), 23.11.20231001.fdd898f`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.17.0`
 - nixpkgs: `/nix/store/5rb11cz8xmv8cdk7b0w80pzczbzk0p26-source`