minigbm: remove stevensd from OWNERS

BUG=None
TEST=None

Change-Id: I4396f90f9e7de7c5d91ad2777e9061735787caa3
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/3593418
Tested-by: David Stevens <stevensd@chromium.org>
Auto-Submit: David Stevens <stevensd@chromium.org>
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org>
Commit-Queue: Yiwei Zhang <zzyiwei@chromium.org>
1 file changed