Support building all variants.

Bug: 143217452
Test: cd external/rust; mma; atest in all TEST_MAPPING subdirs
Change-Id: I9092b122ab2238b6d88b47b26ee786f1c6d86a80
diff --git a/Android.bp b/Android.bp
index eaba2a9..e2b94ca 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,13 +1,14 @@
 // This file is generated by cargo2android.py.
 
-rust_library_host_rlib {
+rust_library {
     name: "libcexpr",
     crate_name: "cexpr",
     srcs: ["src/lib.rs"],
     edition: "2018",
-    rlibs: [
+    rustlibs: [
         "libnom",
     ],
+    host_supported: true,
 }
 
 // dependent_library ["feature_list"]