cfm: Update mojom OWNERS

Chromebox for Meeting is separated from mainline chromium and this causes slight confusion when updating mojoms. As such update the owners group to dedicated members of the CfM team with a process to approve changes to CfM supplemented by a Meet leads review and chromium launch bug security review.

BUG=chromium:1105567
TEST=N/A

Change-Id: I6b1d036ab60a439e6ee5a57091e9ea37642ff917
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2448682
Commit-Queue: Kyle Williams <kdgwill@chromium.org>
Commit-Queue: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Chris Palmer <palmer@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Mattias Nissler <mnissler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823881}

chromeos/services/chromebox_for_meetings/public/mojom/OWNERS

+# Mojo interfaces are only used for Chromebox for Meetings devices; as such
+# they are outside of the scope of the regular mojo security review process.
+
 per-file *.mojom=set noparent
+per-file *.mojom=file://chromeos/components/chromebox_for_meetings/OWNERS
 per-file *.mojom=file://ipc/SECURITY_OWNERS
 per-file *.mojom=file://chromeos/SECURITY_OWNERS