powerhint: Reduce StaleTimeFactor

Reduce StaleTimeFactor for power saving

Bug: 269523712
Test: boot and run uibench
Change-Id: I5d6c88ce46074673c87476d1dcc20c4fd9b9b1e7
Signed-off-by: Ziyi Cui <[email protected]>

powerhint.json

@@ -2144,7 +2144,7 @@
       "EarlyBoost_On": false,
       "EarlyBoost_TimeFactor": 0.0,
       "TargetTimeFactor": 1.0,
-      "StaleTimeFactor": 20.0
+      "StaleTimeFactor": 15.0
     },
     {
       "Name": "REFRESH_90FPS",
@@ -2168,7 +2168,7 @@
       "EarlyBoost_On": false,
       "EarlyBoost_TimeFactor": 0.0,
       "TargetTimeFactor": 1.0,
-      "StaleTimeFactor": 20.0
+      "StaleTimeFactor": 15.0
     },
     {
       "Name": "REFRESH_60FPS",
@@ -2192,7 +2192,7 @@
       "EarlyBoost_On": false,
       "EarlyBoost_TimeFactor": 0.0,
       "TargetTimeFactor": 1.0,
-      "StaleTimeFactor": 20.0
+      "StaleTimeFactor": 15.0
     },
     {
       "Name": "UiHighBoostWithoutPid",