ath10k: use IEEE80211_HW_SW_CRYPTO_CONTROL

The ath10k driver only supports HW crypto (except for management
frames or so - CMAC needs to be done in software). Make it use
the new IEEE80211_HW_SW_CRYPTO_CONTROL flag to ensure mac80211
doesn't erroneously attempt to use software crypto.

Taking through my tree after Kalle's ACK to avoid breaking the
ath10k driver with the next crypto patches.

Acked-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>