dbus: Rename .service file to use the service name as the file name

diff --git a/wpa_supplicant/dbus/dbus-wpa_supplicant.service b/wpa_supplicant/dbus/fi.epitest.hostap.WPASupplicant.service
similarity index 100%
rename from wpa_supplicant/dbus/dbus-wpa_supplicant.service
rename to wpa_supplicant/dbus/fi.epitest.hostap.WPASupplicant.service