Try to make Linux socket ioctls work. Up until now they've only *pretended*
to work, but haven't really due to subtle differences in structs etc.

This is still not perfect (some ioctls are still known not to work, while
others haven't been tested at all), but it's enough to get Debian's ifconfig
to produce relatively sane output.

More work will be needed to get all ioctls (or at least a reasonable subset)
working, and to support the Cisco Aironet config tool mentioned in the PR.

PR: 26546
Submitted by: Doug Ambrisko <ambrisko@ambrisko.com>