Update SKIN_THROTTLING_THRESHOLD to a real value

SKIN_THROTTLING_THRESHOLD was set to 44. However, there are
multiple throttling levels and the first one is 47.

Test: manual
Bug: 30995038
Change-Id: I7c2e5b6a2c045cbc5542c8bd6540613dc1320f64
diff --git a/thermal/thermal.c b/thermal/thermal.c
index 65d84c7..d2171c8 100644
--- a/thermal/thermal.c
+++ b/thermal/thermal.c
@@ -48,7 +48,7 @@
 #define CPU_THROTTLING_THRESHOLD      60
 #define BATTERY_SHUTDOWN_THRESHOLD    60
 // device/google/marlin/thermal-engine-marlin.conf
-#define SKIN_THROTTLING_THRESHOLD     44
+#define SKIN_THROTTLING_THRESHOLD     47
 #define SKIN_SHUTDOWN_THRESHOLD       70
 #define VR_THROTTLED_BELOW_MIN        58