cgroup: make ->pre_destroy() return void

All ->pre_destory() implementations return 0 now, which is the only
allowed return value.  Make it return void.

Signed-off-by: Tejun Heo <[email protected]>
Reviewed-by: Michal Hocko <[email protected]>
Acked-by: KAMEZAWA Hiroyuki <[email protected]>
Acked-by: Li Zefan <[email protected]>
Cc: Balbir Singh <[email protected]>
Cc: Vivek Goyal <[email protected]>

0 files changed, 0 insertions, 0 deletions