PM / cpuidle: Make ladder governor use the "disabled" state flag

For the mechanism introduced by commit cbc9ef02 (PM / Domains: Add
preliminary support for cpuidle, v2) to work with the ladder
governor, that governor should respect the "disabled" state flag
added by that commit.  Change the ladder governor accordingly.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

drivers/cpuidle/governors/ladder.c

@@ -88,6 +88,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
 
 	/* consider promotion */
 	if (last_idx < drv->state_count - 1 &&
+	    !drv->states[last_idx + 1].disabled &&
 	    !dev->states_usage[last_idx + 1].disable &&
 	    last_residency > last_state->threshold.promotion_time &&
 	    drv->states[last_idx + 1].exit_latency <= latency_req) {
@@ -101,7 +102,8 @@ static int ladder_select_state(struct cpuidle_driver *drv,
 
 	/* consider demotion */
 	if (last_idx > CPUIDLE_DRIVER_STATE_START &&
-	    (dev->states_usage[last_idx].disable ||
+	    (drv->states[last_idx].disabled ||
+	    dev->states_usage[last_idx].disable ||
 	    drv->states[last_idx].exit_latency > latency_req)) {
 		int i;