Create a skeleton Rust broadcast radio  HAL

This is to prove that rust broadcast radio HAL can be built and can
run. The skeleton Rust broadcast radio HAL will return UNKNOWN_ERROR
for all APIs.

Bug: 335514024
Test: m android.hardware.broadcastradio-rust-service
Change-Id: I763175b984c130d75cdc9506ba92c8c1b44338b5
diff --git a/broadcastradio/aidl/Android.bp b/broadcastradio/aidl/Android.bp
index 1540944..82ee949 100644
--- a/broadcastradio/aidl/Android.bp
+++ b/broadcastradio/aidl/Android.bp
@@ -36,6 +36,9 @@
             sdk_version: "module_current",
             min_sdk_version: "Tiramisu",
         },
+        rust: {
+            enabled: true,
+        },
     },
     versions_with_info: [
         {
@@ -68,3 +71,10 @@
         latest_android_hardware_broadcastradio + "-java",
     ],
 }
+
+rust_defaults {
+    name: "latest_android_hardware_broadcastradio_rust",
+    rustlibs: [
+        latest_android_hardware_broadcastradio + "-rust",
+    ],
+}