libprocessgroup: fix task_profile_test to correctly detect cgroup v2

Use correct attribute of the mntent to check for cgroup v2 entry.

Bug: 277233783
Change-Id: Ie34b89b610117b8ce043f2f18947273d75618fef
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
1 file changed