Update makefiles for Soong plugin.

Test: manual
Bug: 35570956
Change-Id: I9ff98530878d0067a2a961b17276ac97b2cd9691
diff --git a/transport/Android.bp b/transport/Android.bp
index 4821560..f4ca01c 100644
--- a/transport/Android.bp
+++ b/transport/Android.bp
@@ -25,6 +25,11 @@
     "token/1.0/utils",
 ]
 
+hidl_package_root {
+    name: "android.hidl",
+    path: "system/libhidl/transport",
+}
+
 cc_library {
     name: "libhidltransport",
     vendor_available: true,