net/mlx5: fix ineffective metadata argument adjustment

net/mlx5: fix ineffective metadata argument adjustment

In "dv_xmeta_en" devarg there is an option of dv_xmeta_en=3 which
engages tunnel offload mode. In E-Switch configuration, that mode
implicitly activates dv_xmeta_en=1.

The update according to E-switch support is done immediately after the
first parsing of the devargs, but there is another adjustment later.

This patch moves the adjustment after the second parsing.

Fixes: 4ec6360de37d ("net/mlx5: implement tunnel offload")
Cc: stable@dpdk.org
Signed-off-by: Michael Baum <michaelba@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>