bootstat: Add NTC PMIC shutdown reason.

Add "reboot,ntc,pmic,sub" to kBootReasonMap

Bug: 385228865
Test: Trigger shutdown and validate adb shell bootstat -p
Change-Id: Ic67d3cd915e79eb1ce7feb3e900d387e9d02d641
diff --git a/bootstat/bootstat.cpp b/bootstat/bootstat.cpp
index d476d36..687ffe4 100644
--- a/bootstat/bootstat.cpp
+++ b/bootstat/bootstat.cpp
@@ -469,6 +469,7 @@
     {"reboot,ocp,pmic,if", 237},
     {"reboot,fship", 238},
     {"reboot,ocp,.*", 239},
+    {"reboot,ntc,pmic,sub", 240},
 };
 
 // Converts a string value representing the reason the system booted to an