Update Android.bp by running cargo_embargo

Test: ran cargo_embargo
Change-Id: I79fdb11956bb10c442b274c8cb7696c5a6ae0697
diff --git a/Android.bp b/Android.bp
index 1d34b10..7b4326a 100644
--- a/Android.bp
+++ b/Android.bp
@@ -44,7 +44,7 @@
     crate_name: "futures_macro",
     cargo_env_compat: true,
     cargo_pkg_version: "0.3.30",
-    srcs: ["src/lib.rs"],
+    crate_root: "src/lib.rs",
     edition: "2018",
     rustlibs: [
         "libproc_macro2",