iwlwifi: mvm: clean up number of HW queues

iwlwifi: mvm: clean up number of HW queues

Since switching to mac80211 TXQs, we no longer need to
advertise more hardware queues than ACs, since we don't
even set QUEUE_CONTROL anyway, so the vif->hw_queue[]
mapping array won't be used.

All we need (at least for now) is for hw->queues to
indicate that we have enough queues to handle QoS.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210802172232.80611a3c1ee7.I8a3d2b269421b6d8bada8c12cce3e095e6cfaeed@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>