Revert: ath: add support for special 0x0 regulatory domain

[Bryce Allen]

To handle my two pcengines routers with Compex cards hit by the 0x0 reg 
domain issue, I created some DKMS packages, one for Debian 11 bullseye 
(5.10) and one for the Ubuntu 20.04 HWE kernel (5.11):

https://github.com/bd4/athregd-dkms

Thanks to sparks71 for an example dkms.conf on how to do this. I just 
copied the drivers/net/wireless/ath directory out of the unpacked 
tarball from distro's linux-source package, removed everything except 
for ath9k/10k which are the cards I have and seem to be affected, and 
updated dkms.conf with desired version and modules.

I am using the module param patch from here:
https://gist.github.com/BigNerd95/0be0a5b52a16524a78fc768f0d208a74

It seems to work, but I still get tainted kernel warnings followed by an 
unpleasant stack dump in dmesg.

Cheers,
Bryce