doc: update mlx5 flow count limitations
doc: update mlx5 flow count limitations

Signed-off-by: Ori Kam <dd654df5de18ba542acfaea52fe1a0799392087d@mellanox.com>
Acked-by: Shahaf Shuler <59427d49da6f2b944fbf4cb5ee70ef3ac25f744f@mellanox.com>
Acked-by: Nelio Laranjeiro <2f8dd9032d5b85ca4b53dec8ce664eb6998836be@6wind.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk