BTAudio HAL: Added feature flag for DSA Over LEA

Test: atest VtsHalBluetoothAudioTargetTest
Bug: 270987427
Change-Id: Ifef0b97d20c7c12001b7d04cc7f8ce9da5fb1920
diff --git a/bluetooth/audio/flags/Android.bp b/bluetooth/audio/flags/Android.bp
new file mode 100644
index 0000000..0d18a4d
--- /dev/null
+++ b/bluetooth/audio/flags/Android.bp
@@ -0,0 +1,12 @@
+aconfig_declarations {
+    name: "btaudiohal_flags",
+    package: "com.android.btaudio.hal.flags",
+    srcs: ["btaudiohal.aconfig"],
+}
+
+cc_aconfig_library {
+    name: "btaudiohal_flags_c_lib",
+    aconfig_declarations: "btaudiohal_flags",
+    vendor: true,
+    host_supported: true,
+}