Reduction of networkCreateVpn() permission

Change permission from CONNECTIVITY_INTERNAL to NETWORK_STACK

Test: runtests.sh pass
Test: connect vpn, browse website pass
Change-Id: I9a7d08e08593dda64e901a369bc6431c977f4904
diff --git a/server/NetdNativeService.cpp b/server/NetdNativeService.cpp
index f9a83e4..f9416ec 100644
--- a/server/NetdNativeService.cpp
+++ b/server/NetdNativeService.cpp
@@ -350,7 +350,7 @@
 }
 
 binder::Status NetdNativeService::networkCreateVpn(int32_t netId, bool secure) {
-    ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
+    ENFORCE_PERMISSION(NETWORK_STACK);
     auto entry = gLog.newEntry().prettyFunction(__PRETTY_FUNCTION__).args(netId, secure);
     int ret = gCtls->netCtrl.createVirtualNetwork(netId, secure);
     gLog.log(entry.returns(ret).withAutomaticDuration());