net/mlx5: fix flow table hash list conversion

net/mlx5: fix flow table hash list conversion

For the case when DR is not supported and DV is supported:
	multi-tables feature is off.
	In this case, only table 0 is supported.
	Table 0 structure wrongly was not created what prevented any
	matcher object to be created and even caused crashes.

Create the table hash list in DV case too.
Create table zero empty structure for each domain when DR is not
supported.
Allow NULL DR internal table object to be used.

Fixes: 860897d2895a ("net/mlx5: reorganize flow tables with hash list")
Signed-off-by: Matan Azrad <matan@mellanox.com>