Add Intel QuickAssist (QAT) Support to TrueNas

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I've ended my efforts testing to implement QAT on SCALE.

Here are my highlights:

• Intel just released "new" QAT drivers for the older hardware, which for some ducking retarded reason... does still not even include the basic changes needed for kernel 5.6, 5.7 or 5.8 support.

• Intel also decided to create new drivers for every hardware release (which cover about 70% of the same code, so totally needless frustration), which means we can only support 1 hardware version (because we can only build ZFS based on one QAT driver)

• In the newest drivers intel even added more changes that would break support on newer kernels it seems.

• It is possible to patch the drivers for kernel 5.6, 5.7 and 5.8 support, but that would mean IX has to maintain Intels driver package. Which is a HUGE support burden.

From the above highlights I conclude the following:
Implementing QAT would mean that IX has to pick one hardware revision to support and maintain the QAT drivers and library themselves.
This is not efficient, not sane and just not a good idea at all.

@Adam Goldberg I'm sorry to say, but you can just as well close this suggestion, because it is not going to be implemented.

My Proof-of-Concept for building ZFS with QAT support enabled, has been tested and validated.
Sadly enough this PoC included a patch to get it working on kernel 5.6, but I expect a new intel QAT driver supporting kernel 5.6 somewhere this month.

I'll make sure to get at least ZFS QAT compatibility mergeable when thats available. I don't think there are significant =issues with that, @Ryan Moeller?

To be clear:
This doesn't completely solve this feature by adding it, but at least makes it easier to add. Because people don't have to rebuild the ZFS module themselves (which tends to get messy).

@Ryan Moeller I agree this can't be officially supported for now. However, if we might be able to at least got basic CLI support in (so people don't have to rebuild ZFS) that would make it somewhat more accessable for those of us that want to use it...

Okey, I created something that does at least build...
Needs much additional Work and Feedback, but I did open up a Draft-PR so people can take a look:
https://github.com/truenas/truenas-build/pull/41