Replace the scan results -based implementation with the use of information
from the new BSS table maintained by wpa_supplicant to get a more stable
source of BSS data. Change the use of BSSID as the key for the BSS object
to use the BSS table unique identifier so that multi-SSID APs can be
handled properly.
The D-Bus interface does not really have anything to do with the
wpa_supplicant ctrl_iface interface and as such, this prefix in
dbus files is both confusing and unnecessarily. Make the file names
shorter by removing this prefix.