node: add packet classifier

node: add packet classifier

This node classifies pkts based on packet type and
sends them to appropriate next node. This is node
helps in distribution of packets from ethdev_rx node
to different next node with a constant overhead for
all packet types.

Currently all except non fragmented IPV4 packets are marked
to be sent to "pkt_drop" node.
Performance difference on ARM64 Octeontx2 is -4.9% due to
addition of new node in the path.

Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>