OWNERS: Add nnk and remove dcashman

Bug: 114211287
Test: none
Change-Id: I8abbd10ed292923a29ca9af7a4be15d7529c6bc9
diff --git a/sepolicy/OWNERS b/sepolicy/OWNERS
index 9d3f1b1..e6fbbd4 100644
--- a/sepolicy/OWNERS
+++ b/sepolicy/OWNERS
@@ -1,9 +1,9 @@
 alanstokes@google.com
 bowgotsai@google.com
-dcashman@google.com
 jbires@google.com
 jeffv@google.com
 jgalenson@google.com
+nnk@google.com
 sspatil@google.com
 tomcherry@google.com
 trong@google.com