net/mlx5: add more details to flow dump

net/mlx5: add more details to flow dump

Currently the flow dump provides few information about actions
- just the pointers. Add implementations to display details for
counter, modify_hdr and encap_decap actions.

For counter, the regular flow operation query is engaged and
the counter content information is provided, including hits
and bytes values.For modify_hdr, encap_and decap actions,
the information stored in the ipool objects is dumped.

There are the formats of information presented in the dump:
	Counter: rec_type,id,hits,bytes
	Modify_hdr: rec_type,id,actions_number,actions
	Encap_decap: rec_type,id,buf

Signed-off-by: Haifei Luo <haifeil@nvidia.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>