mac80211: Robust Action frame categories for MFP

IEEE 802.11w/D9.0 introduces a mechanism for Action field Category
values to be used to select which Action frames are Robust. Public and
Vendor-specific categories are marked as not Robust in IEEE 802.11w;
HT will be marked not Robust in IEEE 802.11n. A new Vendor-specific
Protected category is allocated for Robust vendor-specific Action
frames. Another new category, Protected Dual of Action, is introduced
for protecting some existing Public Action frames (e.g., IEEE 802.11y
protected enablement).

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>