Remove hychao@chromium.org from OWNERS files

They are not yet a Chromium committer so they can't Code-Review+1
reviews. Until then they shouldn't be in an OWNERS file.

Change-Id: I3689ec2d4b64eecfb4f761a333ad565363fefed5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1928565
Auto-Submit: Reilly Grant <reillyg@chromium.org>
Commit-Queue: Jenny Zhang <jennyz@chromium.org>
Reviewed-by: Jenny Zhang <jennyz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#717725}

chromeos/audio/OWNERS

 jennyz@chromium.org
-hychao@chromium.org
 # COMPONENT: OS>Kernel>Audio

chromeos/dbus/audio/OWNERS

 jennyz@chromium.org
-hychao@chromium.org