A recent commit added an explicit dependency check on common/mlx5.
For consistency, query dpdk_conf instead of the list of common drivers.
The lists *_drivers should be used only for printing.
Fixes: 3df380f617 ("common/mlx5: fix disabling build")
Suggested-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>