mac80211: introduce channel switch disconnect function

Introduce a disconnect function that can be used when a
channel switch error occurs. The channel switch can request to
block the tx, and so, we need to make sure we do not send a deauth
frame in this case.

Signed-off-by: Nathan Errera <nathan.errera@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20211129152938.cd2a615a0702.I9edb14785586344af17644b610ab5be109dcef00@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>