Revert "mac80211: add AQL support for broadcast packets (#3208) (#3216)" (#3222)

This reverts commit 68c877e7.

It was indicated the patch can lead to excessive throughput with some
devices. Revert this for the stable branch for now.

Link: https://github.com/openwrt/openwrt/commit/1f5fd5cb971166ba57996d41b7ce71e697c186b2#commitcomment-139577735
Link: https://github.com/openwrt/openwrt/commit/95e633efbd1b4ffbbfc2d8abba2b05291f6e9903#commitcomment-139017584



Signed-off-by: David Bauer <mail@david-bauer.net>