net/mlx5: support fine grain dynamic flag

net/mlx5: support fine grain dynamic flag

The inline feature is designed to save PCI bandwidth by copying some
of the data to the wqe. This feature if enabled works for all packets.

In some cases when using external memory, the PCI bandwidth is not
relevant since the memory can be accessed by other means.

This commit introduce the ability to control the inline with mbuf
granularity.

In order to use this feature the application should register the field
name, and restart the port.

Signed-off-by: Ori Kam <orika@mellanox.com>
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>