Revert "Revert "adb: add transport benchmark.""

This reverts commit 2ef56a11.

host_supported is broken in cc_benchmark on Mac, but we probably don't
actually too much about the host benchmarks, so just delete the line.

Bug: http://b/77585931
Test: treehugger
Change-Id: I8898b4037a3faf8e8dee2a99498a6f84e642b92b