net/mlx5: DR, Split chunk allocation to HW-dependent ways

This way we are able to allocate chunk for modify_headers from 2 types:
STEv0 that is allocated from the action area, and STEv1 that is allocating
the chunks from the special area for patterns.

Signed-off-by: Muhammad Sammar <muhammads@nvidia.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Alex Vesker <valex@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>