Make hal_allocator use hal_attribute_hwservice.

If you can get or serve the hal allocator interface,
you should be a hal_allocator_client or
hal_allocator_server.

Bug: 80319537
Test: boot aosp_walleye and (sanity) take photos
Change-Id: Iea14c67c4aa56df7a74ebdb17e99b78b1d3aa105