This is needed since it calls into the driver, which must have the
same context as if we got to destroy an interface through nl80211.
Fix this, and add a direct lockdep assertion so we don't see it
pop up only when the driver calls back to cfg80211.

Fixes: a05829a7 ("cfg80211: avoid holding the RTNL when calling the driver")
Reported-by: syzbot+4305e814f9b267131776@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20210128183454.d31df9cbd7ce.I1beb07c9492f0ade900e864a098c57041e7a7ebf@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>