cfg80211: add ability to override VHT capabilities

For testing it's sometimes useful to be able to
override certain VHT capability advertisement,
add the ability to do that in cfg80211.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/uapi/linux/nl80211.h

@@ -1685,6 +1685,9 @@ enum nl80211_attrs {
 	NL80211_ATTR_PROTOCOL_FEATURES,
 	NL80211_ATTR_SPLIT_WIPHY_DUMP,
 
+	NL80211_ATTR_DISABLE_VHT,
+	NL80211_ATTR_VHT_CAPABILITY_MASK,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,