Use createProcessGroup() from libprocessgroup

This patch prepares for migration of memcg to the v2 cgroup hierarchy by
removing code that hardcodes cgroup paths that will change as the result
of this migration.

Bug: 213617178
Test: Ran alloc-stress inside Cuttlefish.
Change-Id: Ib783d4b619250a2e90db5062cb32110e9f042c5f
Signed-off-by: Bart Van Assche <bvanassche@google.com>
2 files changed