Improve Tuner VTS: Generate LnbLive Combos

This CL allows the VTS to read a vendor's configuration file, determine
if the given devices could support the Lnb Live dataflow, and generate
all combinations of units to run them on corresponding integration tests.

Bug: b/182519645

Test: vts-tradefed run vts --module VtsHalTvTunerTargetTest. Manual
tests with different input configuration files.

Change-Id: Iba5262375b3053e0093f91fd3b05a9ebd42ca7d0