net/mlx5: support matching on ICMP/ICMP6

net/mlx5: support matching on ICMP/ICMP6

On DV/DR flow engine, MLX5 can match on ICMP/ICMP6's code and type field
via FLEX Parser, which can be enabled by config FW using FLEX Parser
profile 2:

mlxconfig -d <mst device> -y set FLEX_PARSER_PROFILE_ENABLE=2

The testpmd commands could be:

  testpmd> flow create 0 ingress pattern eth / ipv4 /
           icmp type is 8 code is 0 / end
	   actions rss queues 0 1 end / end

  testpmd> flow create 0 ingress pattern  eth / ipv6 /
           icmp6 type is 128 code is 0 / end
	   actions rss queues 0 1 end / end

Signed-off-by: Xiaoyu Min <jackmin@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>