wifi: ieee80211: add structs for TBTT information access

The TBTT information can have various lengths with different elements
thare are present. Add definitions for the two types that we are
interested in (i.e. the ones that contain the BSSID).

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230618214436.2a6f8766a3ec.Ic962e28492212cc8ee1eb602b8f07a4ea172fc4a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/linux/ieee80211.h

@@ -4523,6 +4523,28 @@ struct ieee80211_rnr_mld_params {
 #define IEEE80211_RNR_MLD_PARAMS_UPDATES_INCLUDED		0x1000
 #define IEEE80211_RNR_MLD_PARAMS_DISABLED_LINK			0x2000
 
+/* Format of the TBTT information element if it has 7, 8 or 9 bytes */
+struct ieee80211_tbtt_info_7_8_9 {
+	u8 tbtt_offset;
+	u8 bssid[ETH_ALEN];
+
+	/* The following element is optional, structure may not grow */
+	u8 bss_params;
+	u8 psd_20;
+} __packed;
+
+/* Format of the TBTT information element if it has >= 11 bytes */
+struct ieee80211_tbtt_info_ge_11 {
+	u8 tbtt_offset;
+	u8 bssid[ETH_ALEN];
+	__le32 short_ssid;
+
+	/* The following elements are optional, structure may grow */
+	u8 bss_params;
+	u8 psd_20;
+	struct ieee80211_rnr_mld_params mld_params;
+} __packed;
+
 /* multi-link device */
 #define IEEE80211_MLD_MAX_NUM_LINKS	15