owners: Add wltu as owner/maintainer

Change-Id: I1f430661711cd464ba57de98c5342ef5751b1729
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/OWNERS b/OWNERS
index 56a97c3..fadafed 100644
--- a/OWNERS
+++ b/OWNERS
@@ -33,6 +33,7 @@
 
 owners:
 - wak@google.com
+- wltu@google.com
 
 reviewers:
 
@@ -42,3 +43,6 @@
 - name: William Kennington
   email: wak@google.com
   discord: wak
+- name: Willy Tu
+  email: wltu@google.com
+  discord: wltu