mac80211: allow all interfaces types to handle RX action frames

Eliminate the vif.type check in ieee80211_rx_h_action.  This check is
unnecessary (these action frames can be handled by all interface types) and
currently prevents, for example, AP interfaces from handling BACK action frames
such as ADDBA and DELBA requests.

Signed-off-by: Andrey Yurovsky <andrey@cozybit.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>