Make async-stream-impl available to product and vendor

Bug: 270690570

Test: mma in external/rust/crates
Change-Id: I00ced0e74b69e415d438725e18f35fafc0feab5e
diff --git a/Android.bp b/Android.bp
index 86e3496..0516029 100644
--- a/Android.bp
+++ b/Android.bp
@@ -32,4 +32,6 @@
         "libquote",
         "libsyn",
     ],
+    product_available: true,
+    vendor_available: true,
 }