Correct the offload capability and update comment(AIDL)

- Add some comments to describe the supported scenario
- Correct the config from mono to stereo, when only one device is
  connected, mono only need one audio channel, for stereo case,
  support 2 audio channels.

Tag: #feature
Bug: 203535499
Bug: 150670922
Test: make build
Change-Id: Id3ea1e96a6b4fd7a209a015fb5c475465e300cdb
diff --git a/bluetooth/audio/utils/aidl_session/BluetoothAudioCodecs.cpp b/bluetooth/audio/utils/aidl_session/BluetoothAudioCodecs.cpp
index 516ebe8..b857fb8 100644
--- a/bluetooth/audio/utils/aidl_session/BluetoothAudioCodecs.cpp
+++ b/bluetooth/audio/utils/aidl_session/BluetoothAudioCodecs.cpp
@@ -132,9 +132,13 @@
 // Stores the supported setting of audio location, connected device, and the
 // channel count for each device
 std::vector<std::tuple<AudioLocation, uint8_t, uint8_t>>
-    supportedDeviceSetting = {std::make_tuple(stereoAudio, 2, 1),
-                              std::make_tuple(monoAudio, 1, 2),
-                              std::make_tuple(monoAudio, 1, 1)};
+    supportedDeviceSetting = {
+        // Stereo, two connected device, one for L one for R
+        std::make_tuple(stereoAudio, 2, 1),
+        // Stereo, one connected device for both L and R
+        std::make_tuple(stereoAudio, 1, 2),
+        // Mono
+        std::make_tuple(monoAudio, 1, 1)};
 
 template <class T>
 bool BluetoothAudioCodecs::ContainedInVector(