GitLab

Add explicit instructions on how to add a userid to
the `kvm` group.

Bug: None
Change-Id: Iea1432c2213a9b8f1b5875c91727963e83cc747a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2097158
Commit-Queue: Scott Graham <scottmg@chromium.org>
Reviewed-by: Scott Graham <scottmg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749205}