audio: Add IBluetooth core interface

This interface corresponds to BT-specific functions
of the IPrimaryDevice in the HIDL HAL.

Bug: 205884982
Test: atest VtsHalAudioCoreTargetTest
Change-Id: I5f52d65e06f42e1a5fb2e51d27b79e94fe423eaa
diff --git a/audio/aidl/default/Android.bp b/audio/aidl/default/Android.bp
index 8cd56c0..6f23636 100644
--- a/audio/aidl/default/Android.bp
+++ b/audio/aidl/default/Android.bp
@@ -62,6 +62,7 @@
     export_include_dirs: ["include"],
     srcs: [
         "AudioPolicyConfigXmlConverter.cpp",
+        "Bluetooth.cpp",
         "Config.cpp",
         "Configuration.cpp",
         "EngineConfigXmlConverter.cpp",