ANDROID: GKI: add fields required to enable CONFIG_TRANSPARENT_HUGEPAGE

Devices with plenty of RAM might benefit from THP usage. Added fields
would allow to enable CONFIG_TRANSPARENT_HUGEPAGE without affecting ABI.

Bug: 168269341
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ieb644a8da5377383d514197ee02d7bfd6f1d346d