Support building host/vendor variants for tflite.

Test: Compile
Bug: 178230712
Change-Id: If69d369b05cd9e547d90aa799b043634b7bc6344
diff --git a/Android.bp b/Android.bp
index d8443e7..33d8bf1 100644
--- a/Android.bp
+++ b/Android.bp
@@ -16,6 +16,7 @@
     name: "tensorflow_headers",
     export_include_dirs: ["."],
     vendor_available: true,
+    host_supported: true,
     sdk_version: "current",
     apex_available: [
         "com.android.neuralnetworks",