Align LibAudioHal V2 and V4 for factorisation

In order to merge the two version, they must first align as much
as possible.

Test: playback music, assistant
Change-Id: If517cc3f4646a224af3e9b3d42b68a75f1801b39
Signed-off-by: Kevin Rocard <krocard@google.com>
diff --git a/media/libaudiohal/2.0/EffectBufferHalHidl.h b/media/libaudiohal/2.0/EffectBufferHalHidl.h
index 31e0087..5c70743 100644
--- a/media/libaudiohal/2.0/EffectBufferHalHidl.h
+++ b/media/libaudiohal/2.0/EffectBufferHalHidl.h
@@ -28,6 +28,7 @@
 using android::hidl::memory::V1_0::IMemory;
 
 namespace android {
+namespace V2_0 {
 
 class EffectBufferHalHidl : public EffectBufferHalInterface
 {
@@ -71,6 +72,7 @@
     status_t init();
 };
 
+} // namespace V2_0
 } // namespace android
 
 #endif // ANDROID_HARDWARE_EFFECT_BUFFER_HAL_HIDL_H