Make async-trait available to product and vendor

Bug: 270690570

Test: mma in external/rust/crates
Change-Id: Id22bb867aac634985c2e912bc6e67da8009ea90a
diff --git a/Android.bp b/Android.bp
index e9ff15b..c7d70bb 100644
--- a/Android.bp
+++ b/Android.bp
@@ -49,4 +49,6 @@
         "libquote",
         "libsyn",
     ],
+    product_available: true,
+    vendor_available: true,
 }