Update Android.bp by running cargo_embargo

Test: ran cargo_embargo
Change-Id: Id0111df50b09584ee2ef17d597553557c92e1666
diff --git a/Android.bp b/Android.bp
index b472399..0565299 100644
--- a/Android.bp
+++ b/Android.bp
@@ -23,7 +23,7 @@
     crate_name: "merge_derive",
     cargo_env_compat: true,
     cargo_pkg_version: "0.1.0",
-    srcs: ["src/lib.rs"],
+    crate_root: "src/lib.rs",
     edition: "2018",
     rustlibs: [
         "libproc_macro2",