rtw88: remove unused vif pointer in struct rtw_vif

As driver can easily get vif with container_of(), we can
just remove it.
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtw88/mac80211.c

@@ -153,7 +153,6 @@ static int rtw_ops_add_interface(struct ieee80211_hw *hw,
 	u8 bcn_ctrl = 0;
 
 	rtwvif->port = port;
-	rtwvif->vif = vif;
 	rtwvif->stats.tx_unicast = 0;
 	rtwvif->stats.rx_unicast = 0;
 	rtwvif->stats.tx_cnt = 0;

drivers/net/wireless/realtek/rtw88/main.h

@@ -736,7 +736,6 @@ struct rtw_bf_info {
 };
 
 struct rtw_vif {
-	struct ieee80211_vif *vif;
 	enum rtw_net_type net_type;
 	u16 aid;
 	u8 mac_addr[ETH_ALEN];