Update security string to 2016-09-07 to platform and CTS for September   respin am: cc5148493f am: 637fa9c4c5
am: 5ed4043667

Change-Id: I14818a4b4220874c816fbe9dc1d150b598f030e5
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index c493cc4..b8620c1 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -73,7 +73,7 @@
   # Can be an arbitrary string, but must be a single word.
   #
   # If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-  PLATFORM_SECURITY_PATCH := 2016-09-05
+  PLATFORM_SECURITY_PATCH := 2016-09-07
 endif
 
 ifeq "" "$(PLATFORM_BASE_OS)"