staging: rtl8723bs: Remove yield call, replace with cond_resched()

Remove yield() call. Yield does not guarantee progress, cond_resched()
is a safer alternative

Signed-off-by: Thomas Avery <tavery321@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_pwrctrl.c

@@ -701,7 +701,7 @@ void LPS_Leave_check(
 	bReady = false;
 	start_time = jiffies;
 
-	yield();
+	cond_resched();
 
 	while (1) {
 		down(&pwrpriv->lock);