ath10k: fix CAC regression

Commit 54846213 ("ath10k: fix interrupt storm") introduced a
regression. The condition responsible for bringing up monitor vdev was broken
and it was never started for CAC so effectivelly CAC would not detect radar
pulses.

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