ath10k: disable STA kickout in FW

Currently ath10k is not using STA KICKOUT firmware functionality.
In order to avoid unwanted WMI_PEER_STA_KICKOUT_EVENT event this functionality
should be disabled when not used.

Signed-off-by: Marek Puzyniak <marek.puzyniak@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>