Add a PACKET_KEEPALIVE_OFFLOAD permission.

Bug: 23884210
Change-Id: I0f9207ac9b9c07c676f64f2748905e523e891501
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index c8bb675..b8b6444 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -1056,6 +1056,11 @@
     <permission android:name="android.permission.CONNECTIVITY_INTERNAL"
         android:protectionLevel="signature|privileged" />
 
+    <!-- Allows a system application to access hardware packet offload capabilities.
+         @hide -->
+    <permission android:name="android.permission.PACKET_KEEPALIVE_OFFLOAD"
+        android:protectionLevel="signature|privileged" />
+
     <!-- @SystemApi
          @hide -->
     <permission android:name="android.permission.RECEIVE_DATA_ACTIVITY_CHANGE"