net/mlx5: Expose SW ICM related device memory capabilities

Add SW ICM related fields to the device memory capabilities
structure and sw ownership capability in flow table properties.

The currently supported SW ICM types are steering and header modify
and the changes exposes the device memory capabilities for each
of these two types.

SW ICM memory can be allocated by SW and then be accessed by RDMA
operations for direct management of the HW packet handling tables.

Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Reviewed-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>