PNS: Add PNS_IF_GET_ASSET_IND to the default netIC gateway task packet filter.

Add PNS_IF_GET_ASSET_IND to the default netIC gateway task packet filter.

If a netIC host application registers to the netIC (to receive PNS Stack stack indications), then the service PNS_IF_GET_ASSET_IND is not forwarded automatically any more to the netIC host.
The netIC gateway task handles this packet by itself. If the netIC host still wants to receive this packet, it must be explicit subscribed by the netIC packet filter.