What to do wrt wireless kernel drivers?

[diederikdehaas]

Currently we indiscriminately include all (USB and) wireless drivers of the installer kernel.

With the current 4.9 kernel that means ~ 10MB worth of drivers x 2 kernels (rpi1 and rpi2) = ~20MB
With a 5.10 kernel, the size of wireless drivers grew to ~ 36MB x 2 kernels = ~72MB

This means the size of the installer will double in size, just to accommodate new wireless drivers, without any new functionality.
As new drivers are added constantly to the kernel, and rarely will any one be removed, this problem will only grow bigger over time.

Including the wireless kernel drivers for hardware present on some RPi models is a nobrainer as far as I'm concerned.
But any other wireless driver is debatable and that's exactly the purpose of this issue.
So I want you to make a case why driverX should be included too (by replying to this issue).

This doesn't mean that the installer will fail for any wireless device which does not have its drivers builtin.
There are other ways to provide additional drivers. I have had the following code snippet in my installer-config.txt:

if [ -f /bootfs/config/wireless-drivers.tar.gz ] ; then
  echo -n "Loading drivers... "
  tar -zxf /bootfs/config/wireless-drivers.tar.gz -C /
  echo "OK"
  echo -n "Running depmod to update the list of modules... "
  /sbin/depmod -a
  echo "OK"
fi

Where wireless-drivers.tar.gz was an archive file I constructed myself. That is (some) work, but that can be facilitated.
It can also be part of build.sh, where the excluded drivers are automatically put in wireless-drivers.tar.gz and that file can then be offered as an optional download next to the installer itself.

Providing an option to optionally load (external) (wireless) drivers was actually (one of) the idea(s) behind the drivers_to_load config variable.
See also #175 (comment) and #319