mac80211: remove old legacy legacy drivers

mac80211: remove old legacy legacy drivers

Get rid of drivers that are either limited to 802.11b/g or don't even support
cfg80211/mac80211. Most of these are either limited to boards that we don't even
support anymore because of firmware size, or were only used for custom hacks by
a really small number of users in the past.
Let's get rid of those to reduce the maintenance effort and the number of useless
packages

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