implement WPA2 Stations Key handling

Implement the required support for extrace the cipher
suite settings from the the RS Information Element and
set the station key based on the 802.11 Station Key
CAPWAP message element.

Group Key update handling is currently not implemented nor is
Station Key update handling.

src/common/binding/ieee80211/ieee80211.h

@@ -420,6 +420,9 @@ struct ieee80211_ie_erp {
 	uint8_t params;
 } STRUCT_PACKED;
 
+/* 802.11 RSN information element */
+#define IEEE80211_IE_RSN_INFORMATION							48
+
 /* 802.11 Extended Supported Rates information element */
 #define IEEE80211_IE_EXTENDED_SUPPORTED_RATES			50
 #define IEEE80211_IE_EXTENDED_SUPPORTED_MIN_LENGTH		1