ANDROID: GKI: Add symbols to abi_gki_aarch64_oplus

Add some file nodes to control and tune the memcg status in the memory
cgroup, need add some symbols to abi_gki_aarch64_oplus.

Leaf changes summary: 5 artifacts changed
Changed leaf types summary: 0 leaf type changed
Removed/Changed/Added functions summary: 0 Removed, 0 Changed, 3 Added functions
Removed/Changed/Added variables summary: 0 Removed, 0 Changed, 2 Added variables

3 Added functions:

  [A] 'function int cgroup_add_legacy_cftypes(cgroup_subsys*, cftype*)'
  [A] 'function mem_cgroup* mem_cgroup_from_id(unsigned short int)'
  [A] 'function void unregister_memory_notifier(notifier_block*)'

2 Added variables:

  [A] 'cgroup_subsys memory_cgrp_subsys'
  [A] 'static_key_true memory_cgrp_subsys_enabled_key'

Bug: 204860045
Signed-off-by: Liujie Xie <xieliujie@oppo.com>
Change-Id: I69805dcdfbe363c13031ae0a9556761b71a67428