Add bialpio@ to OWNERS of xr-related directories

Change-Id: I735de5c7f56cad4fec89dd3033ad6748a875ebee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1575360
Commit-Queue: Piotr Bialecki <bialpio@chromium.org>
Auto-Submit: Piotr Bialecki <bialpio@chromium.org>
Reviewed-by: David Dorwin <ddorwin@chromium.org>
Reviewed-by: Bill Orr <billorr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#652617}
4 files changed