net/mlx5: fix matcher field usage for metadata entities

net/mlx5: fix matcher field usage for metadata entities

Matcher is flow table related structure providing the flow pattern
to be translated directly in hardware controlling data. This structure
includes the metadata register c0 field, that might be engaged to
support META and MARK related flow items and actions. Also, this
register might be used by kernel to specify the source vport index.
In this case (if kernel uses the field) the register c0 is split
into two 16-bit subfields - one for META/MARK items and another
to handle vport.

The actual configuration is queried by PMD from kernel in runtime
and depending on the mask returned by kernel the PMD can use upper
or lower half of register c0 field. This patch adds the missing
support for upper half. This missed support caused the non-operational
META/MARK items on some kernel configurations.

Fixes: e554b672aa05 ("net/mlx5: support flow tag")
Cc: stable@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>