wireguard kernel module doesn't build for armhf

The wireguard kernel module can't be compiled for armhf. It fails with /bin/sh: scripts/basic/fixdep: not found. Essentially !1234 (merged) is not working since the last kernel update for some reason (which means, the fixdep program is installed as x86_64 ELF binary in the armhf package of linux-postmarketos-stable-dev, which causes the error above).

This is blocking building binary packages in the repo, because it's stuck at this package right now. I'm on it.

And also I want to improve the package building infrastructure in general, so errors like this become known early. Now that I have consistent time every week day to hack on pmOS, I'll put up a detailed plan of what I will work on pretty soon (so it becomes more transparent, and we can talk about what needs to be prioritized etc).