init starts servicemanagers in "default" mount ns

servicemanager/hwservicemanager are pre-apexd services but still wants
to see VINTF fragments from APEXes, especially from /data.

Like ueventd, these services need to be started in "default" mount
namespace.

Bug: 237672865
Test: m && boot
Change-Id: I0266c5be5530a1a07f8ffa23a26186d45a55613f
2 files changed