Updating Linux code with current recommendations

So I've been going through some of the files, running the code through the linter shellcheck.net, then updating the code with the recommendations.

Specifically, I've done all the /etc/init.d/ files related to ZFS. The pools are now imported more quickly. I also did my drive read-ahead code and my drive LED remapping code... one update that kept the variable local rather than global was recommended, which helps speed things up when unloading that code on reboot.

Slowly but surely I'm ironing out the little bugs that slow the machine down and throw spurious errors.

Now I just have to figure out how to:

  1. keep the machine from throwing the warning: amdgpu: SRAT table not found... that's the textbook example of a spurious warning, since NUMA-enabled machines such as mine don't use the ACPI SRAT (Static Resource Affinity Table).

  2. fix the WARNING! power/level is deprecated; use power/control instead warn, which is related to power management on USB-connected devices.

  3. fix the bdi 7:6: the stable_pages_required attribute has been removed. Use the stable_writes queue attribute instead. warn, deprecated in kernel 5.10:

grep -R . /sys/block/*/bdi/stable_pages_required