Export cgroup_add_legacy_cftypes and a helper function to allow vendor module to expose additional files in the memory cgroup hierarchy.
Bug: 192052083
Signed-off-by: Liujie Xie <xieliujie@oppo.com>
(cherry picked from commit f41a95eadca98506e627b21f5cc73332bba4d95c)
(cherry picked from commit bf24c43b7f90290d2ac6f8163b43ab00f8f820b9)
Change-Id: Ie2b936b3e77c7ab6d740d1bb6d70e03c70a326a7
Signed-off-by: lvwenhuan <lvwenhuan@oppo.com>