chromebox_for_meetings: Update OWNERS files

Bug: b:175644742
Test: N/A
Change-Id: I64b50791912d8a74a590459f6038bafa6522c6f1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2605346
Auto-Submit: Kyle Williams <kdgwill@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Kyle Williams <kdgwill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#839472}

chrome/browser/chromeos/chromebox_for_meetings/OWNERS

+file://chromeos/components/chromebox_for_meetings/OWNERS

chromeos/components/chromebox_for_meetings/OWNERS

-jrt@google.com
-kdgwill@google.com
-ziegs@google.com
+kdgwill@chromium.org

chromeos/services/chromebox_for_meetings/OWNERS

+file://chromeos/components/chromebox_for_meetings/OWNERS