cpuidle: menu: Tweak threshold use in get_typical_interval()

To prepare get_typical_interval() for subsequent changes, rearrange
the use of the data point threshold in it a bit and initialize that
threshold to UINT_MAX which is more consistent with its data type.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Reviewed-by: Christian Loehle <christian.loehle@arm.com>
Tested-by: Christian Loehle <christian.loehle@arm.com>
Tested-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Link: https://patch.msgid.link/8490144.T7Z3S40VBb@rjwysocki.net

Author: rafaeljw

drivers/cpuidle/governors/menu.c

@@ -116,7 +116,7 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev);
  */
 static unsigned int get_typical_interval(struct menu_device *data)
 {
-	unsigned int max, divisor, thresh = INT_MAX;
+	unsigned int max, divisor, thresh = UINT_MAX;
 	u64 avg, variance, avg_sq;
 	int i;
 
@@ -129,8 +129,8 @@ static unsigned int get_typical_interval(struct menu_device *data)
 	for (i = 0; i < INTERVALS; i++) {
 		unsigned int value = data->intervals[i];
 
-		/* Discard data points above the threshold. */
-		if (value > thresh)
+		/* Discard data points above or at the threshold. */
+		if (value >= thresh)
 			continue;
 
 		divisor++;
@@ -186,7 +186,7 @@ static unsigned int get_typical_interval(struct menu_device *data)
 	if ((divisor * 4) <= INTERVALS * 3)
 		return UINT_MAX;
 
-	thresh = max - 1;
+	thresh = max;
 	goto again;
 }