mac80211: clean up ht capability handling, drop the use of the ht_capab list,...

mac80211: clean up ht capability handling, drop the use of the ht_capab list, use individual variables instead

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@40682 3c298f89-4303-0410-b956-a3cf2f4a3e73