common/mlx5: fix code arrangement in tag allocation

common/mlx5: fix code arrangement in tag allocation

Flow tag action is supported only when the driver has DR or DV support.
The tag allocation is adjusted to the modes DV or DR.

In case both DR and DV are not supported in the system, the driver
handles static code for error report.
This error code, wrongly, was compiled when DV is supported while in
this case it cannot be accessed at all.

Ignore the aforementioned static error code in case of DV by
preprocessor commands rearrangement.

Fixes: cbb66daa3c85 ("net/mlx5: prepare Direct Verbs for Direct Rule")
Cc: stable@dpdk.org
Signed-off-by: Michael Baum <michaelba@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>