Convert NetdClient to use Soong

Android.mk => Android.bp

This makes loading netd_client into other Soong modules easier.

Bug: 33159037
Test: make clean && make full -j30
Change-Id: I86f18c51faeacf43f6e8ba965a8b1f76e4594ebc
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..8e6ca0f
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,6 @@
+cc_library_headers {
+    name: "libnetd_client_headers",
+    export_include_dirs: ["include"],
+}
+
+subdirs = ["*"]