Update OT documentation to reference RuntimeEnabled

Bug: 934451
Change-Id: I62b2969964b1f38d1e066f842ef5635286dcea27
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1671407
Reviewed-by: Jason Chase <chasej@chromium.org>
Commit-Queue: Allen Robinson <arobins@chromium.org>
Auto-Submit: Allen Robinson <arobins@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672052}
1 file changed