Revert "mac80211: disable uAPSD if all ACs are under ACM"

This reverts commit 24aa11ab.

That commit was wrong since it uses data that hasn't even been set
up yet, but might be a hold-over from a previous connection.

Additionally, it seems like a driver-specific workaround that
shouldn't have been in mac80211 to start with.

Cc: stable@vger.kernel.org
Fixes: 24aa11ab ("mac80211: disable uAPSD if all ACs are under ACM")
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>