Update makefiles for hidl_interface.

Bug: 35570956
Test: pass
Change-Id: Ib6adcc0016e19e77593f24167b32a555c5b500c9
diff --git a/Android.bp b/Android.bp
index 878f5ad..5417899 100644
--- a/Android.bp
+++ b/Android.bp
@@ -1,8 +1,4 @@
-// This is an autogenerated file, do not edit.
-subdirs = [
-    "net/netd/1.0",
-    "net/netd/1.0/vts/functional",
-    "wifi/keystore/1.0",
-    "wifi/keystore/1.0/default",
-    "wifi/keystore/1.0/vts/functional",
-]
+hidl_package_root {
+    name: "android.system",
+    path: "system/hardware/interfaces",
+}