zfs-linux SRU build support against hwe kernels

[Dimitri John Ledkov]

[ Impact ]

 * hwe kernels keep on changing

 * jammy zfs-linux 2.1.5 upstream releases + cherry-picks is quite old, thus a jump to 2.1.12
   or 2.2 has potential to break userspace

 * Instead cherry-pick patches that continue to enable building zfs-dkms against hwe kernels, if
one desires to use dkms from the archive, rather than prebuilt modules that all of Ubuntu kernels ship.

 * the cherry-picks area gainst config/* code (autoconf/m4) and kernel code (module/ & include/), without any changes to userspace tooling or fixes.

[ Test Plan ]

 * verify zfs-dkms module builds from source against v5.15, v5.19, v6.2, v6.3 kernels on jammy
 * verify existing zsys installs continue to work
 * verify kernel team zfs tests-suites continue to work with v5.15 kernel

[ Where problems could occur ]

 * majority of diff is in config macros to detect different compatible kernel APIs and ABIs and use an appropriate one. there are changes to uidmap handling for v6.3 kernels, however it is mostly ignored by userspace without intruducing new feature. LXD will need to be double checked, as it may assume this driver version seems to accept uidmap mount options - which it then ignores.

 * Note this is still at feature parity with Lunar's upload 2.1.9-2ubuntu1.1, despite having partial kernel driver only build compat with v6.3 - as v6.3 kernels are not expected to land in lunar, and will not land in jammy until after mantic release. Mantic already has much newer 2.2.x series zfs-linux.

[ Other Info ]

 * This is similar to previous zfs-linux SRUs we have performed in the past.

[Steve Langasek (vorlon)]

> if one desires to use dkms from the archive, rather than prebuilt modules that all of Ubuntu kernels ship.

I am failing to see how this is compatible with the Ubuntu SRU policy.

[Steve Langasek (vorlon)]

An upload of zfs-linux to jammy-proposed has been rejected from the upload queue for the following reason: "no response from uploader to incomplete bug status for >1m".

[Dimitri John Ledkov (xnox)]

we literary need this for oem kernel in the jammy archive