remove pools without a bootfs from BOOTFS variable creation

[prometheanfire]

Use the same method used in zfs-load-key.

Closes: #7085

[prometheanfire]

gimme a min to test this, should have a verified result some time tonight, @WoefulDerelict mind testing on a multi-pool system?

[WoefulDerelict]

Not at all. I will nab this and test it shortly.

[prometheanfire]

it looks like two things happened with systemd-236

1. the systemctl command changed from /usr/bin to /bin
2. systemd-ask-password isn't working now

[WoefulDerelict]

Arch Linux appears to be forcing systemctl to /usr/bin/ along with the rest of the toolchain. Unfortunate that systemd-ask-password is failing.

I've synced up to 522db29275b81c18c2bf53a95efa1aedeb13b428, cherry picked the patch and tested it on the same system with success. The system booted without the zfs-import-cache.service throwing any errors.

[WoefulDerelict]

/bin is a symlink to /usr/bin on Arch Linux systems so the proposed change is unlikely to break anything.

[prometheanfire]

is it a symlink within the dracut shell as well? (lsinitrd doesnt show that for me)

drwxr-xr-x   2 root     root            0 Jan 26 23:58 bin
lrwxrwxrwx   1 root     root           15 Jan 26 23:58 bin/awk -> ../usr/bin/gawk

[prometheanfire]

ok, my problem was that plymouth needed to be rebuilt with the new paths for systemd. this PR should be good to go.

[WoefulDerelict]

By default Arch Linux uses an initramfs CPIO image generated with mkinitcpio. /bin/systemctl resolves properly and zfs-import-cache.service starts without error.

dracult is an option; however, not one I've tested or have something set up to test with.

[codecov]

Codecov Report

Merging #7089 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #7089      +/-   ##
=========================================
- Coverage    75.6%   75.6%   -0.01%     
=========================================
  Files         296     296              
  Lines       95661   95664       +3     
=========================================
- Hits        72328   72327       -1     
- Misses      23333   23337       +4

Flag	Coverage Δ
#kernel	74.8% <ø> (-0.24%)	⬇️
#user	67.93% <ø> (+0.07%)	⬆️

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[behlendorf]

@prometheanfire @WoefulDerelict if I understand correctly from the comment above this PR has been tested and is ready to merge? Can you please confirm.

[prometheanfire]

confirmed here