LinuxKPI: 802.11: turn on debugfs for iwlwifi and rtw88

Make iwlwifi compile with debugfs after the last updates and turn it on
for both iwlwifi and rtw88 in order to be able to get at least some
useful information on driver/firwmare state.

Sponsored by: The FreeBSD Foundation

(cherry picked from commit 07f6575585bf69ae48dffe87c4578057ae4782d8)