Add zhin@ to src/codegen OWNERS

Change-Id: Ia8eed6717385c7f662677ff8a117b04bf64aa452
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2693287
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72720}

src/codegen/OWNERS

@@ -10,9 +10,9 @@ jkummerow@chromium.org
 leszeks@chromium.org
 mslekova@chromium.org
 mvstanton@chromium.org
+mythria@chromium.org
 neis@chromium.org
 rmcilroy@chromium.org
 sigurds@chromium.org
 solanes@chromium.org
-titzer@chromium.org
-mythria@chromium.org
+zhin@chromium.org