rtlwifi: rtl8723be: Remove set but not used variable 'b_last_is_cur_rdlstate'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/wireless/realtek/rtlwifi/rtl8723be/dm.c: In function 'rtl8723be_dm_check_edca_turbo':
drivers/net/wireless/realtek/rtlwifi/rtl8723be/dm.c:998:7: warning:
 variable 'b_last_is_cur_rdlstate' set but not used [-Wunused-but-set-variable]

It's never used and can be removed.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtlwifi/rtl8723be/dm.c

@@ -995,12 +995,9 @@ static void rtl8723be_dm_check_edca_turbo(struct ieee80211_hw *hw)
 	u32 edca_be = 0x5ea42b;
 	u32 iot_peer = 0;
 	bool b_is_cur_rdlstate;
-	bool b_last_is_cur_rdlstate = false;
 	bool b_bias_on_rx = false;
 	bool b_edca_turbo_on = false;
 
-	b_last_is_cur_rdlstate = rtlpriv->dm.is_cur_rdlstate;
-
 	cur_txok_cnt = rtlpriv->stats.txbytesunicast - last_txok_cnt;
 	cur_rxok_cnt = rtlpriv->stats.rxbytesunicast - last_rxok_cnt;