iwlwifi: mvm: enable TX on new CSA channel before disconnecting

When moving to the new channel, we block TX until we hear the
first beacon. if it is not heard, we proceed to disconnect.
Since TX is blocked (without mac80211 being aware of it) the frame
is stuck, resulting with queue hang.

Instead, reenable TX before reporting on the connection loss.
As we are on the new channel, there is no problem with that,
even if the original CSA had quiet mode.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210330162204.eb4f2ff1b863.Ib16238106b33d58b2b7688dc6297018b915ecef4@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>