Add test case for BSSID hotlist and fix wifi scanner test cases

For the BSSID hotlist testing config file should have dependencies
information such as interest Bssids to be tracked for 2g, 5g and DFS
and test bed information as per sample bssidhotlist.config file.
BSSIDs set for tracking should be part of the shield box which is
connected throgh second attenuator listed in config file.

For wifi scanner, "isolated environment test" is included. In this test
scripts will attenuate both attenuator to 90db and make isolated environment
for device. Before running this test make sure that attenuators
information is provided in config file

Change-Id: Ic132f24b996475b7b9181ee2e580b36d899cb446
1 file changed