Set the Security Patch level with Oct 1 for MNC

- MNC currently has security patches from the August OEM bulletin with patch date of Sep 1 plus only critical fixes from September OEM bulletin
- To be cherry-picked if picking up remaining fixes from September OEM bulletin to MNC

Change-Id: I2d1ba9c5a893727962f3f1837df1dd9df49e44f5
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 691a4bd..9bb5a2c 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -103,7 +103,7 @@
   # 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 := 2015-09-01
+  PLATFORM_SECURITY_PATCH := 2015-10-01
 endif
 
 ifeq "" "$(PLATFORM_BASE_OS)"