cpuidle: lpm-levels: Do not predict LPM for isolated cpus

Prediction can select shallower low power mode for isolated
cpu based on historical data.

Do not predict LPMs for isolated cpus.

Change-Id: I998008ef3c578c1dccfacae8513a15dfbe397e16
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
diff --git a/drivers/cpuidle/lpm-levels.c b/drivers/cpuidle/lpm-levels.c
index 03fce64..0bff951 100644
--- a/drivers/cpuidle/lpm-levels.c
+++ b/drivers/cpuidle/lpm-levels.c
@@ -642,7 +642,7 @@
 				next_wakeup_us = next_event_us - lvl_latency_us;
 		}
 
-		if (!i) {
+		if (!i && !cpu_isolated(dev->cpu)) {
 			/*
 			 * If the next_wake_us itself is not sufficient for
 			 * deeper low power modes than clock gating do not