AudioDevices HAL uses "default" service name

The getService() and registerAsService() methods of interface objects
now have default parameters of "default" for the service name. HALs
will not have to use any service name unless they want to register
more than one service.

Test: builds

Bug: 33844934
Change-Id: I7ccbf802fcded790b4be325f36a34a3af6b42052
diff --git a/audio/2.0/default/service.cpp b/audio/2.0/default/service.cpp
index 8b608c8..6dcf7ec 100644
--- a/audio/2.0/default/service.cpp
+++ b/audio/2.0/default/service.cpp
@@ -38,7 +38,7 @@
 int main(int /* argc */, char* /* argv */ []) {
     configureRpcThreadpool(16, true /*callerWillJoin*/);
     android::status_t status;
-    status = registerPassthroughServiceImplementation<IDevicesFactory>("audio_devices_factory");
+    status = registerPassthroughServiceImplementation<IDevicesFactory>();
     LOG_ALWAYS_FATAL_IF(status != OK, "Error while registering audio service: %d", status);
     status = registerPassthroughServiceImplementation<IEffectsFactory>("audio_effects_factory");
     LOG_ALWAYS_FATAL_IF(status != OK, "Error while registering audio effects service: %d", status);