staging: rtl8723bs: core: remove set but not used 'pwrpriv'

Fix the following gcc warning:

drivers/staging/rtl8723bs/core/rtw_mlme.c:1100:24: warning: variable
‘pwrpriv’ set but not used [-Wunused-but-set-variable]
   struct pwrctrl_priv *pwrpriv;
                        ^~~~~~~
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200427032342.27211-7-yanaijie@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_mlme.c

@@ -1097,9 +1097,6 @@ inline void rtw_indicate_scan_done(struct adapter *padapter, bool aborted)
 	    (!adapter_to_pwrctl(padapter)->bInSuspend) &&
 	    (!check_fwstate(&padapter->mlmepriv,
 			    WIFI_ASOC_STATE|WIFI_UNDER_LINKING))) {
-		struct pwrctrl_priv *pwrpriv;
-
-		pwrpriv = adapter_to_pwrctl(padapter);
 		rtw_set_ips_deny(padapter, 0);
 		_set_timer(&padapter->mlmepriv.dynamic_chk_timer, 1);
 	}