adjust the cgroup bug to use n-cpu

the cgroup bug is currently tracking via n-sched. The same errors
are in n-cpu (they originate in n-cpu) and n-sched is not being
tracked in logstash in grenade yet.

Change-Id: If0b386ababc62fe61a4f20d9f2c08554dabacb09
Related-Bug: #1295876