Update Security String to 2020-02-05
bug:146378789
(cherry picked from commit 9b687f04caa32b6794867f2568e02968c318d482)

Change-Id: I6b896901a581c1450e55d74bfa99a7d2d182fecc
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 6e72f2c..7e96214 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -250,7 +250,7 @@
     #  It must be of the form "YYYY-MM-DD" on production devices.
     #  It must match one of the Android Security Patch Level strings of the Public Security Bulletins.
     #  If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-      PLATFORM_SECURITY_PATCH := 2020-02-01
+      PLATFORM_SECURITY_PATCH := 2020-02-05
 endif
 .KATI_READONLY := PLATFORM_SECURITY_PATCH