Clean up permission validation in EthernetServiceImpl am: a4e8e77e24 am: 023d842244 am: 3611bee278

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/net/ethernet/+/2018836

Change-Id: I9f85cc34425e5200ea3410df5c1cfcc9e8a84e99
tree: 543e46a38c3367fd69566a280cd80ea4c8e08ed6
  1. service-t/
  2. tests/