Support building all variants.

Bug: 143217452
Test: cd external/rust; mma; atest in all TEST_MAPPING subdirs
Change-Id: I06e44bcb90bfd90d4f5ceeb453a6c1b9af151954
diff --git a/Android.bp b/Android.bp
index e5bd1fa..640eea3 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,6 +1,6 @@
 // This file is generated by cargo2android.py --run --dependencies --features=bytes.
 
-rust_library_host_rlib {
+rust_library_host {
     name: "libprotobuf",
     crate_name: "protobuf",
     srcs: ["src/lib.rs"],
@@ -8,7 +8,7 @@
     features: [
         "bytes",
     ],
-    rlibs: [
+    rustlibs: [
         "libbytes",
     ],
 }