Connect and enable root before running each testcase

- Enable16KbTest is flaky for aosp targets. Make sure that device
is connected and with root each time before and after running the
test.
- Add OWNERS file Enable16KbTest

Test: atest -c Enable16KbTest
Bug: 396984821
Change-Id: Ifffb73496b0947dda13a4022733677bd645b7e16