[NETD-TC#12] Fix dependency on libtraffic_controller

1. Add visibility for libtraffic_control
2. Add com.android.tethering into apex_available statement

Bug: 202086915
Test: m; flash; boot
Change-Id: I817e22c24dd205f09ef62a2a7ff85b2a970f6d3a
diff --git a/staticlibs/netd/Android.bp b/staticlibs/netd/Android.bp
index c3f9374..a615ec1 100644
--- a/staticlibs/netd/Android.bp
+++ b/staticlibs/netd/Android.bp
@@ -48,6 +48,7 @@
     ],
     apex_available: [
         "com.android.resolv",
+        "com.android.tethering",
     ],
     min_sdk_version: "29",
 }
@@ -97,6 +98,7 @@
         ndk: {
             apex_available: [
                 "//apex_available:platform",
+                "com.android.tethering",
             ],
             // This is necessary for the DnsResovler tests to run in Android Q.
             // Soong would recognize this value and produce the Q compatible aidl library.