Update system/security owners

Test: n/a
Change-Id: I197d2350eac5de29eac2e37ff7dae2a5814bc3df
diff --git a/OWNERS b/OWNERS
index 03e5769..6fdb550 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1,5 +1,4 @@
 alanstokes@google.com
-cbrubaker@google.com
 drysdale@google.com
 eranm@google.com
 hasinitg@google.com
@@ -8,4 +7,5 @@
 kroot@google.com
 sethmo@google.com
 swillden@google.com
+trong@google.com
 zeuthen@google.com