Enable IPv6 datagram filter by default from NcpBase constructor (#1256)

* Enable IPv6 datagram filter by default from `NcpBase` constructor

* Enable RLOC pass through when in Tunnel mode

examples/drivers/windows/otLwf/tunnel.c

@@ -102,6 +102,20 @@ otLwfTunInitialize(
         KeSetEvent(&pFilter->TunWorkerThreadStopEvent, IO_NO_INCREMENT, FALSE);
     }
 
+    // Make sure to enable RLOC passthrough
+    Status =
+        otLwfCmdSetProp(
+            pFilter,
+            SPINEL_PROP_THREAD_RLOC16_DEBUG_PASSTHRU,
+            SPINEL_DATATYPE_BOOL_S,
+            TRUE
+        );
+    if (!NT_SUCCESS(Status))
+    {
+        LogError(DRIVER_DEFAULT, "Enabling RLOC pass through failed, %!STATUS!", Status);
+        goto error;
+    }
+
     // TODO - Query other values and capabilities
 
 error:

src/ncp/ncp_base.cpp

@@ -514,6 +514,7 @@ NcpBase::NcpBase(otInstance *aInstance):
     otSetReceiveIp6DatagramCallback(mInstance, &NcpBase::HandleDatagramFromStack, this);
     otSetLinkPcapCallback(mInstance, &NcpBase::HandleRawFrame, static_cast<void*>(this));
     otSetIcmpEchoEnabled(mInstance, false);
+    otSetReceiveIp6DatagramFilterEnabled(mInstance, true);
 
     mUpdateChangedPropsTask.Post();