Bluetooth  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; verify HAL still works

In support of b/33844934

Change-Id: Icc006a71b41bcd03fe4a04ee92503e76ff07cd77
diff --git a/bluetooth/1.0/default/service.cpp b/bluetooth/1.0/default/service.cpp
index a3c3cad..fa5106f 100644
--- a/bluetooth/1.0/default/service.cpp
+++ b/bluetooth/1.0/default/service.cpp
@@ -25,5 +25,5 @@
 using android::hardware::defaultPassthroughServiceImplementation;
 
 int main() {
-  return defaultPassthroughServiceImplementation<IBluetoothHci>("bluetooth");
+  return defaultPassthroughServiceImplementation<IBluetoothHci>();
 }