Update Android.bp by running cargo_embargo

Test: ran cargo_embargo
Change-Id: I22dfe8987c61324d58ecea0a36f4133705382c2b

Android.bp

diff --git a/Android.bp b/Android.bp
index 8903060..c72a53c 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,5 +1,7 @@
 // This file is generated by cargo_embargo.
-// Do not modify this file as changes will be overridden on upgrade.
+// Do not modify this file after the first "rust_*" or "genrule" module
+// because the changes will be overridden on upgrade.
+// Content before the first "rust_*" or "genrule" module is preserved.
 
 // TODO: Add license.
 rust_test {