Add chromeos-bsp-mistral to upstart oom score exceptions

This check is breaking mistral-cq.
See:
https://luci-milo.appspot.com/ui/p/chromeos/builders/cq/mistral-cq/b8840249940947384448/overview

BUG=b:195145703
TEST=None

Change-Id: Icb97ec6349b7a9f98720c62c28e50c5af9ce7b53
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3064841
Tested-by: Dennis Kempin <denniskempin@google.com>
Owners-Override: Dennis Kempin <denniskempin@google.com>
Reviewed-by: George Engelbrecht <engeg@google.com>
Reviewed-by: Aileen Cheng <chengaileen@google.com>
Commit-Queue: Aileen Cheng <chengaileen@google.com>
1 file changed