qca6174 with wmi-tlv firmware uses offloaded
beaconing scheme (i.e. templates). This requires a
little different approach when implementing CSA.

Add missing code to update CS count and report CSA
completion to mac80211. Without it channel switch
was never finished.

To avoid races during interface teardown data_lock
has been used to protect is_up and is_started so
they can be compared against before scheduling
count down work.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>