Expand set of OWNERS to infra/config/global for lower review latency.

R=hinoka@chromium.org, iannucci@chromium.org, jchinlee@chromium.org, smut@google.com, vadimsh@chromium.org

Change-Id: Iaf3c26162afbd8cdefcf49073f3c8900bc23911e
Reviewed-on: https://chromium-review.googlesource.com/957964Reviewed-by: smut <smut@google.com>
Reviewed-by: Ryan Tseng <hinoka@chromium.org>
Reviewed-by: Vadim Shtayura <vadimsh@chromium.org>
Reviewed-by: Jao-ke Chin-Lee <jchinlee@chromium.org>
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542330}

infra/config/global/OWNERS

 dpranke@chromium.org
 estaab@chromium.org
+hinoka@chromium.org
+iannucci@chromium.org
+jchinlee@chromium.org
 nodir@chromium.org
+smut@google.com
+tandrii@chromium.org
+vadimsh@chromium.org