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/Android.bp b/audio/aidl/Android.bp
index ef51361..e69306e 100644
--- a/audio/aidl/Android.bp
+++ b/audio/aidl/Android.bp
@@ -112,6 +112,7 @@
         "android/hardware/audio/core/AudioMode.aidl",
         "android/hardware/audio/core/AudioPatch.aidl",
         "android/hardware/audio/core/AudioRoute.aidl",
+        "android/hardware/audio/core/IBluetooth.aidl",
         "android/hardware/audio/core/IConfig.aidl",
         "android/hardware/audio/core/IModule.aidl",
         "android/hardware/audio/core/IStreamCallback.aidl",