fs_mgr: add dvander@ to OWNERS

Test: n/a
Change-Id: I7ac90d2dd54f53b12b67c77bc452946156fdcccf
diff --git a/fs_mgr/OWNERS b/fs_mgr/OWNERS
index 817a0b8..cbbd3bc 100644
--- a/fs_mgr/OWNERS
+++ b/fs_mgr/OWNERS
@@ -1,2 +1,3 @@
 bowgotsai@google.com
+dvander@google.com
 tomcherry@google.com