rtw89: ser: leave lps with mutex

Calling rtw89_leave_lps() should hold rtwdev::mutex.
So, fix it.
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220704023453.19935-5-pkshih@realtek.com

drivers/net/wireless/realtek/rtw89/ser.c

@@ -153,7 +153,10 @@ static void ser_state_run(struct rtw89_ser *ser, u8 evt)
 	rtw89_debug(rtwdev, RTW89_DBG_SER, "ser: %s receive %s\n",
 		    ser_st_name(ser), ser_ev_name(ser, evt));
 
+	mutex_lock(&rtwdev->mutex);
 	rtw89_leave_lps(rtwdev);
+	mutex_unlock(&rtwdev->mutex);
+
 	ser->st_tbl[ser->state].st_func(ser, evt);
 }