Add post_update.sh and regenerate .bp

* Regenerate .bp with new dependent package versions.
* Include out/*.rs in src/link.rs.

Bug: 169119477
Test: tools/external_updater/updater.sh update rust/crates/clang-sys
Test: mm in external/rust/crates/clang-sys
Change-Id: I56d1df7d2dacab5611bc6f7e78d4b7f039b77d8a
diff --git a/Android.bp b/Android.bp
index 35de6b8..3824501 100644
--- a/Android.bp
+++ b/Android.bp
@@ -2,7 +2,6 @@
 
 rust_library_host {
     name: "libclang_sys",
-    // has rustc warnings
     crate_name: "clang_sys",
     srcs: ["src/lib.rs"],
     edition: "2015",
@@ -30,6 +29,7 @@
 }
 
 // dependent_library ["feature_list"]
+//   cfg-if-0.1.10
 //   glob-0.3.0
-//   libc-0.2.71
-//   libloading-0.6.2
+//   libc-0.2.77
+//   libloading-0.6.3