This allows automated testing of the wpa_supplicant D-Bus interface. The
instance controlling wlan0 registers with D-Bus if dbus-daemon was
started successfully. This is only used in VM testing, i.e., not when
run-tests.sh is used on the host system with D-Bus running for normal
system purposes.
Signed-off-by: Jouni Malinen <j@w1.fi>