staging: rtl8723bs: core: rtw_wlan_util: Remove unused variable 'start_seq'

Fixes the following W=1 kernel build warning(s):

 drivers/staging/rtl8723bs/core/rtw_wlan_util.c: In function ‘process_addba_req’:
 drivers/staging/rtl8723bs/core/rtw_wlan_util.c:1774:11: warning: variable ‘start_seq’ set but not used [-Wunused-but-set-variable]
 from drivers/staging/rtl8188eu/core/rtw_wlan_util.c:12:

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-staging@lists.linux.dev
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210414181129.1628598-20-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_wlan_util.c

@@ -1716,7 +1716,7 @@ int update_sta_support_rate(struct adapter *padapter, u8 *pvar_ie, uint var_ie_l
 void process_addba_req(struct adapter *padapter, u8 *paddba_req, u8 *addr)
 {
 	struct sta_info *psta;
-	u16 tid, start_seq, param;
+	u16 tid, param;
 	struct recv_reorder_ctrl *preorder_ctrl;
 	struct sta_priv *pstapriv = &padapter->stapriv;
 	struct ADDBA_request *preq = (struct ADDBA_request *)paddba_req;
@@ -1726,8 +1726,6 @@ void process_addba_req(struct adapter *padapter, u8 *paddba_req, u8 *addr)
 	psta = rtw_get_stainfo(pstapriv, addr);
 
 	if (psta) {
-		start_seq = le16_to_cpu(preq->BA_starting_seqctrl) >> 4;
-
 		param = le16_to_cpu(preq->BA_para_set);
 		tid = (param>>2)&0x0f;