Expose ConnectivityManager#TYPE_NONE as SystemApi

Support wifi mainline module usage.

Bug: 135998869
Test: Build and make system-api-stubs-docs-update-current-api
      atest FrameworksNetTests
Change-Id: Ia496aaeaf74fa44764640fd2b97c417509e040aa
diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index 4002e8d..26114be 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -517,7 +517,7 @@
      * The absence of a connection type.
      * @hide
      */
-    @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 130143562)
+    @SystemApi
     public static final int TYPE_NONE        = -1;
 
     /**