Backport test fixes for recent kernels

Now with failures due to being run in a container out of the way, amd64 package has passed on laniakea, but the arm64 still had a few tests failing. Turns out that those were all false positives due to changes in recent kernel headers, so I've backported the fixes.

There's a small chance that not all of the failures are fixed there, but pushing the new package to laniakea seems to be by far the fastest way to find out from those available to me...