Support building all variants.

Bug: 143217452
Test: cd external/rust; mma; atest in all TEST_MAPPING subdirs
Change-Id: I080762a7f55d7d0aa21868ebc73581c8b15ac125
diff --git a/Android.bp b/Android.bp
index 702752c..d643d02 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,6 +1,6 @@
 // This file is generated by cargo2android.py.
 
-rust_library_rlib {
+rust_library {
     name: "liblog_rust",
     stem: "liblog",
     host_supported: true,
@@ -13,7 +13,7 @@
     flags: [
         "--cfg atomic_cas",
     ],
-    rlibs: [
+    rustlibs: [
         "libcfg_if",
     ],
 }