CEC VTS: Improve testIsConnected test

Add validation to the response from isConnected HAL API. Expected
response is true if the DUT has a physical address and false otherwise.

Bug: 157402557
Test: vts-tradefed run commandAndExit vts-hal-tv -m VtsHalTvCecV1_0Host
Change-Id: I7611aedec5990e3f4fa1603ee76856f11e811486
1 file changed